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Engine Control Module Scan Tool Information (RPO LMM)

WARNING: This page is about a different car, the 2010 GMC Sierra, 2010 GMC Cab & Chassis Sierra, 2010 Chevrolet Silverado, and 2010 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The Engine Control Module Scan Tool Data List contains all engine-related parameters that are available on the scan tool. The list is arranged in alphabetical order. A given parameter may appear in any one of the data lists, and in some cases may appear more than once, or in more than one data list in order to group certain related parameters together.

Use the Engine Scan Tool Data List only after the following is determined:

The scan tool values from a properly running engine may be used for comparison with the engine you are diagnosing. The Engine Scan Tool Data List represents values that would be seen on a normally running engine.

IMPORTANT: A scan tool that displays faulty data should not be used. The scan tool concern should be reported to the manufacturer. Use of a faulty scan tool can result in misdiagnosis and unnecessary parts replacement.

Only the parameters listed below are referenced in this service manual for use in diagnosis.

Engine Control Module Scan Tool Data

Parameter System State Expected Value Description
Base Operating Conditions:  Engine Idling/Radiator Hose Hot/Park or Neutral/Closed Loop/Accessories Off
4WD Low Signal 4WD Low ON Enabled This parameter displays the state of the transfer case based on the signal from the four wheel drive (4WD) low switch. The scan tool will display Enabled or Disabled. Enabled indicates the transfer case is in 4WD low gear and the 4WD low switch is closed, completing the low signal circuit. Disabled indicates the transfer case is not in 4WD low gear and the 4WD low switch is open.
Invalid indicates there is no 4WD low.
4WD Low OFF Disabled
No 4WD Low Invalid
4WD Signal 4WD ON Enabled This parameter displays the state of the transfer case based on the signal from the front axle indicator switch. The scan tool will display Enabled or Disabled. Enabled indicates the front axle is locked in 4WD and the front axle indicator switch is closed, supplying voltage to the controller on the axle switch signal circuit. Disabled indicates the transfer case is not in 4WD and the front axle indicator switch is open.
4WD OFF Disabled
5-volt Reference 1 Circuit Status - OK This parameter will display OK if the circuit is good or Fault if a short to ground, short to B+ or open circuit is present.
5-volt Reference 2 Circuit Status - OK This parameter will display OK if the circuit is good or Fault if a short to ground, short to B+ or open circuit is present.
5-volt Reference 3 Circuit Status - OK This parameter will display OK if the circuit is good or Fault if a short to ground, short to B+ or open circuit is present.
A/C Compressor Cycling Switch - Normal Normal/Low Pressure
A/C Relay Command A/C OFF OFF This parameter displays the commanded state of the air conditioning (A/C) clutch relay control circuit. The scan tool will display ON or OFF. ON indicates the A/C clutch relay control circuit is being grounded by the control module, allowing voltage to the A/C compressor clutch. OFF indicates the A/C clutch relay is not being commanded on by the control module.
A/C ON ON
A/C Request Signal A/C ON YES The scan tool displays YES/NO. The HVAC module receives an input request when the HVAC module is turned On.
A/C OFF NO
A/C High side Pressure Sensor A/C OFF 1.43 Volts The scan tool displays 0-5 volts. The voltage applied to the ECM input for the A/C refrigerant pressure sensor.
A/C ON 2.39 Volts
A/C High side Pressure Sensor A/C OFF 500-2,220 kPa (72-31 psi) The scan tool displays 0-3450 kPa (0-500 psi). The voltage applied to the ECM input from the A/C refrigerant pressure sensor is converted to a pressure value.
A/C ON 300-1,220 kPa (43-17 psi)
A/C High Side Pres. Sw. - Normal The scan tool displays High Press./Normal, the state of the A/C high side pressure.
A/C OFF for WOT A/C ON/WOT NO The scan tool displays YES/NO. The state of the A/C request related to wide open throttle.
A/C ON/Not WOT Yes
A/C Pressure Disable - NO The scan tool displays YES/NO. The state of the A/C refrigerant pressure sensor and circuitry.
A/C Disengage 1-8 History A/C ON Reason for A/C Disengagement This parameter indicates the reason the A/C compressor was disengaged. The reasons displayed are: None, A/C Pressure, Eng Spd, Batt Voltage, Stall Prevention, RPM Unstable, WOT, Launch Perf, Coolant Hot.
Ambient Air Temperature - Varies Outside temperature at any given altitude expressed in degrees
APP Indicated Angle Accelerator pedal not actuated 0% This parameter displays the angle of the accelerator pedal as calculated by the control module using the signals from the accelerator pedal position sensors. The accelerator pedal position (APP) indicated angle is a range of values indicating a low percentage when the accelerator pedal is not depressed to a high percentage when the accelerator pedal is fully depressed.
Accelerator pedal fully actuated 100%
APP Sensor 1 Accelerator pedal not actuated 0.7-1.2 Volts This parameter displays the voltage signal sent to the control module from APP sensor 1 of the APP sensor assembly. APP sensor 1 is a range of values indicating a low voltage when the accelerator pedal is not depressed to a high voltage when the accelerator pedal is fully depressed.
Accelerator pedal fully actuated 4.2-4.5 Volts
APP Sensor 1 Indicated Position Accelerator pedal not actuated 0.0% This parameter displays the angle of the APP sensor 1 as calculated by the control module using the signal from the APP sensor 1. APP sensor 1 is a range of values indicating a low percentage when the accelerator pedal is not depressed to a high percentage when the accelerator pedal is fully depressed.
Accelerator pedal fully actuated 100%
APP Sensor 2 Accelerator pedal at rest position 0.3-0.5 Volts This parameter displays the voltage signal sent to the control module from APP sensor 2 of the APP sensor assembly. APP sensor 2 is a range of values indicating a low voltage when the accelerator pedal is not depressed to a high voltage when the accelerator pedal is fully depressed.
Accelerator pedal at WOT 2.0-2.5 Volts
APP Sensor 2 Indicated Position Accelerator pedal at rest position 0.0% This parameter displays the angle of the APP sensor 2 as calculated by the control module using the signal from the APP sensor 2. APP sensor 2 is a range of values indicating a low percentage when the accelerator pedal is not depressed to a high percentage when the accelerator pedal is fully depressed.
Accelerator pedal at WOT 100%
Balancing Rate Cyl. 1-8 - Varies These parameters display the adjustment in fuel volume for each cylinder as calculated by the control module. The scan tool will display a negative balancing rate if the fuel volume is lowered. The scan tool will display a positive balancing rate if the fuel volume is increased.
BARO - Varies with altitude This parameter displays the barometric pressure as calculated by the control module using the signal from the MAP sensor measured when the ignition is turned on with the engine not running. The control module will update the barometric pressure during wide-open throttle (WOT) conditions.
Base Injector Fuel Rate - Varies It display base calculate rate fuel delivers. The rate is calculated in cubic millimeters.
Boost Pressure Sensor - Varies This parameter shows the turbocharger boost pressure in kPa.
BPP Circuit Signal Released OK/Fault/Invalid This parameter displays the status of the brake pedal position circuit.
BPP Signal Released Applied / Release This parameter displays the status of the brake pedal as determined by the ECM.
Commanded A/F Equivalence Ratio - 1 Equivalence numbers greater than one represent excess fuel in the fuel air mix. Equivalence numbers less than one represent a deficiency of fuel in the fuel air mix for complete combustion. The equivalence ratio will be reported as one when the vehicle is in Closed Loop.
Component Monitor Complete This Ignition - No This parameter displays the component monitor completion status during the current driving/monitoring cycle.
Component Monitor Enabled This Ignition - No This parameter displays the component monitor completion status during the current driving/monitoring cycle.
Coolant Level Switch - OK This parameter displays the level of engine coolant as determined by the control module. The control module determines the level of the coolant using the signal from a switch used to monitor the engine coolant level. The scan tool will display low when the engine coolant level is low. The scan tool will display OK when the coolant level is correct.
Cooling Fan Command - % This parameter displays the cooling fan duty cycle.
Cooling Motor Fan Command - % This parameter displays the cooling fan duty cycle.
Crank Request Signal - No This parameter displays the state of the crank request input to the control module from the ignition switch. The scan tool will display Yes when the ignition switch is in the Crank position. The scan tool will display No when the ignition switch is in any other position.
Cruise Control Active - Inactive This parameter displays the status of the cruise control system as determined by the control module. The scan tool will display Yes when the cruise control system is in control of vehicle speed. The scan tool will display No when the cruise control system is not operating.
Cruise Disengage 1-8 History Cruise ON Reason for Cruise Disengagement These parameters indicate the last 8 reasons the ECM disengaged the cruise control. Reason 1 contains the most recent reason. The reasons may include the following: Brake Pedal Initialize, Cancel, Clutch, Coast Disengage, Coast Speed Low, TAC Inhibit, Accel Rate, Decel Rate, High Speed, Illegal Mode, Low Speed, None, Cruise Sw OFF, Over Set Speed, S/C On Speed Hi, ECM Inhibit, Simul S/C-R/A, TCS, Under Set Speed, DLC Override, Memory DTC, Eng Run Time, Engine Speed, DTC Set, RPM Limit, First Gear, APP Override, Low Voltage, D Whl Spd Low, D Whl Spd Hi, Cruise S/S, Cruise Sw Data, ECT Overtemp, VSES, Trans. DTC, BPP Data, BPP DTC, Park Brake, ACC Inhibit, ACC Brake DTC, ACC Option, ACC Brake Inop, PTO Active.
Cruise On/Off Switch - Off This parameter displays the state of the On/Off switch input to the control module. The scan tool will display On when the cruise On/Off switch is On. The scan tool will display OFF when the cruise ON/OFF switch is OFF.
Cruise Resume/Accel Switch - Inactive This parameter displays the state of the Resume/Accel switch input to the control module When the cruise control switch is in the On position and the Resume/Accel switch is activated, the scan tool displays On. When the Resume/Accel switch is released the scan tool displays Off.
Cruise Set/Coast Switch - Inactive This parameter displays the state of the Set/Coast switch input to the control module from the cruise control system. When the cruise control switch is in the on position and the Set/Coast switch is activated, the scan tool displays On. When the Set/Coast switch is released the scan tool displays Off.
Current Fuel Type - Diesel The parameter will display diesel as the current fuel type.
Des. TC Vane Pos. Ctrl. Solenoid - Varies This parameter displays the desired current draw of the turbocharger vane position control solenoid valve as calculated by the control module. The scan tool will display a high value if the solenoid is commanded open, and a lower value when the solenoid is commanded closed.
Desired EGR Position - 22-28% This parameter displays the position of the exhaust gas recirculation (EGR) valve commanded by the control module. The scan tool will display 0 percent when the control module is commanding the EGR valve closed. The scan tool will display a higher percentage when the EGR valve is commanded open.
Desired Fan Speed - Varies This parameter displays the fan idle speed in RPM as commanded by the control module. The control module compensates for various engine loads in order to maintain the desired fan speed at idle. This parameter is not valid unless the engine is running.
Desired Fuel Rail Pressure - Varies This parameter displays the desired fuel rail pressure as calculated by the control module. This value is calculated based on engine speed, engine load, and sensor inputs. The scan tool will display a higher value at higher engine speeds and loads, and a lower value at idle.
Desired IAF Valve Position - 100 % This parameter will display the position of the intake air flow valve and it will display it in percentage.
Desired Idle Speed - 680 RPM This parameter displays the engine idle speed in RPM as commanded by the control module. The control module compensates for various engine loads in order to maintain the desired engine speed at idle. This parameter is not valid unless the engine is running.
Desired TC Boost - Varies This parameter displays the TC Boost pressure as commanded by the control module. This parameter shows the turbocharger boost pressure in kPa.
Desired TC Vane Position - Varies This parameter displays the position of the turbocharger vane position sensor as the turbocharger vane position is commanded by the control module. The scan tool will display 0 percent when the control module is commanding the vanes open. The scan tool will display a higher percentage when the vanes are commanded closed.
Distance Since DTC Cleared - Varies This parameter displays the distance accumulated since an emission diagnostic trouble code was cleared. The scan tool will display increasing distance as the vehicle is driven.
Distance Since Last DPF Regeneration - Varies This parameter will display the amount of vehicle travel after a DPF regeneration. This parameter will be displayed in km/miles.
DPF Lamp Command - Off This parameter will display the status of the IPC mounted DPF status light. This parameter will display On/Off.
DPF Pressure Sensor - Varies This parameter will display the voltage differential between the front and rear pressures at the DPF as calculated by the ECM. This will be displayed in volts. As the DPF becomes restricted the differential pressure increases and the voltage we get higher.
DPF Soot Mass - Varies This parameter displays the amount of calculated soot in exhaust particulate filter. This parameter will be displayed in grams.
EC Ignition Relay Command - ON This parameter displays the commanded state of the engine control (EC) ignition relay control circuit. The scan tool will display ON or OFF. ON indicates the EC ignition relay control circuit is being grounded by the control module, allowing voltage to other control module circuits and systems. OFF indicates the EC ignition relay is not being commanded ON by the control module.
ECM Challenge Status - Valid This parameter displays the condition of the ECM code challenge to the BCM.
ECM in VTD Fail / Enable No This parameter displays the status of the vehicle theft deterrent system.
ECT Sensor 1 - 85-105°C/185-220°F This parameter displays the temperature of the engine coolant based on the input from the engine coolant temperature (ECT) sensor. When the coolant temperature is low, the scan tool will display a low temperature. When the coolant temperature is high, the scan tool will display a high temperature.
EGR Cooler Temp. Sensor 1 - Varies This parameter will display the exhaust temperature entering the EGR Cooler. The EGR Temp Sensor 1 temperature will be warmer than the EGR Temp Sensor 2.
EGR Cooler Temp. Sensor 2 - Varies This parameter will display the exhaust temperature exiting the EGR Cooler. The EGR Temp Sensor 2 temperature will be cooler than the EGR Temp Sensor 1.
EGR Learned Minimum Position - 0% This parameter displays the learned minimum position of the EGR valve as calculated by the control module. The scan tool will display a low value if the current closed EGR position is the same as the last ignition cycle. The scan tool will display a higher value if the EGR valve has closed at a new position.
EGR Monitor Complete This Ignition - Varies This parameter displays the completion status during the current driving/monitoring cycle of the non-continuous legislated emission related monitor. The states include Yes and No.
EGR Monitor Enabled This Ignition - Varies This parameter displays the completion status during the current driving/monitoring cycle of the non-continuous legislated emission related monitor. The states include Yes and No.
EGR Pos. Lrn. This Run Cycle Yes / No - This parameter displays the condition of the Learned EGR position by the ECM.
EGR Position Variance % - This parameter displays the EGR position variance from the last learned position.
EGR Position Sensor - 22-28% This parameter displays EGR valve position as calculated by the control module based on an input from the EGR valve position sensor. The scan tool will display a lower value when the EGR valve is closed, and a higher value when the EGR valve is open.
EGR Position Sensor - 1.75 Volts This parameter displays the voltage signal received from the EGR valve position sensor by the control module. The scan tool will display a lower value when the EGR valve is closed, and a higher value when the EGR valve is open.
EGR Solenoid Command - 3-15% This parameter displays the duty cycle commanded by the control module for the EGR valve. The scan tool will display a high percentage when the EGR valve is commanded open. The scan tool will display a low percentage when the EGR valve is commanded closed.
EGT Sensor 1 - Varies This parameter will display the exhaust temperature before the DPF. When the exhaust temperature is low, the scan tool will display a low temperature. When the exhaust temperature is high, the scan tool will display a high temperature.
EGT Sensor 2 - Varies This parameter will display the exhaust temperature after the DPF. When the exhaust temperature is low, the scan tool will display a low temperature. When the exhaust temperature is high, the scan tool will display a high temperature.
Engine Load - Varies This parameter displays the engine load in percent based on inputs to the control module from various engine sensors. The scan tool will display a low percentage when the engine is at idle with little or no load. The scan tool will display a high percentage when the engine is running at a high RPM under a heavy load.
Engine Oil Level Switch - OK This parameter displays the status of the engine oil level switch as determined by the control module. The control module uses this information to turn on the low engine oil lamp if the engine oil level remains approximately 1 quart low for a sufficient amount of time. The scan tool will display Low when the engine oil level is low. The scan tool will display OK when the engine oil level is correct.
Engine Oil Life Remaining - Varies This parameter displays the amount engine oil life remaining before requiring an oil change based on calculations by the control module. The scan tool will display lower values as the engine oil life approaches 0 miles.
Engine Oil Pressure Switch - OK This parameter displays the state of the EOP as determined by the control module. The control module monitors the EOP switch to determine if the EOP is sufficient. The scan tool will display low when the EOP is below a predetermined value.
Engine Oil Pressure Sensor - Varies This parameter displays the pressure of the engine oil as calculated by the control module using a signal from the engine oil pressure (EOP) sensor. The scan tool will display oil pressure when the engine is running. The engine oil pressure sensor has a range of values indicating a low value when the oil pressure is low to a high value when the oil pressure is high.
Engine Run Time - Varies This parameter displays the time elapsed since the engine was started. The scan tool will display the time in hours, minutes and seconds. The engine run time will reset to zero when the engine stops running.
Engine Run Time Since Last DPF Regeneration - Varies This parameter displays the total of time since the last regen. This parameter will be displayed in hours, minutes and seconds.
Engine Speed - 680 RPM This parameter displays the speed of the crankshaft as determined by the control module using an input from the CKP sensor. The scan tool will display a high value at high engine speeds and a low value at low engine speeds.
Engine Torque - Varies This parameter displays the estimated amount of torque that is delivered from the engine. The scan tool displays engine torque in N.m (lb-ft). The ECM sends the engine torque information to the TCM via the high speed GMLAN serial data line.
EPM Inhibit Reason None - This parameter displays the reason for EPM inhibit.
Exhaust Brake Switch, if equipped - Off This parameter displays the input status of the exhaust brake switch to the control module. The scan tool will display ON or OFF. ON indicates the exhaust brake switch is closing the exhaust brake request circuit to the control module. OFF indicates the exhaust brake switch is open.
Ext. Travel BPP Ckt Signal Released - This parameter displays the status of the Ext Travel BPP signal circuit.
Ext. Travel BPP Signal Released - This parameter displays the status of the Ext. Travel Brake Pedal Position sensor.
Fan Speed - Varies This parameter displays the speed of the fan as determined by the control module. The scan tool will display a high value at high engine speeds and a low value at low engine speeds.
FC Ckt Open Test Status OK This parameter displays the status of the fan control circuit open test.
FC Relay 3 Circuit Status Open - OK This parameter displays the diagnostic state of the output driver for the cooling fan relay 1 control circuit. The scan tool will display OK, Incomplete, Short B+, Short Gnd/Open. The scan tool will display OK if the circuit is operating correctly.
FRP Regulator Command - 35-40% This parameter displays the fuel rail pressure regulator duty cycle as commanded by the control module. The scan tool will display a lower value for a higher commanded fuel pressure, and a higher value for a lower commanded fuel pressure.
Fuel Filter Life Remaining - Varies This parameter displays the fuel filter life remaining before requiring an fuel filter change. This number is calculated by the control module based on many inputs and is displayed as a percent. The lower the percentage, the sooner the next fuel filter change will be required.
Fuel Level Sensor - Varies This parameter displays the voltage from the sensor used to monitor the fuel level inside the fuel tank. The scan tool will display a low voltage reading when that the fuel level in the tank is low or near empty. The scan tool will display a high voltage reading when the fuel level in the tank is high or near full.
Fuel Level Sensor Rear Tank - Varies This parameter displays the voltage from the sensor used to monitor the fuel level inside the fuel tank. The scan tool will display a low voltage reading when that the fuel level in the tank is low or near empty. The scan tool will display a high voltage reading when the fuel level in the tank is high or near full.
Fuel Pump Relay Command - Varies with fuel level This parameter displays the commanded state of the fuel pump relay control circuit. The fuel pump relay should be on when the scan tool indicates the Fuel Pump Relay Command is On. The fuel pump relay should be off when the scan tool indicates the Fuel Pump Relay Command is Off.
Fuel Rail Pressure Sensor - 35-40 MPa (5076-5801 psi) This parameter displays the fuel rail pressure as calculated by the control module. This value is calculated based on engine speed, engine load, and sensor inputs. The scan tool will display a higher value at higher engine speeds and loads, and a lower value at idle.
Fuel Rail Pressure Sensor - Varies This parameter displays the voltage signal sent to the control module from the sensor used to measure the fuel rail pressure. The scan tool will display a low voltage at idle and high voltage when pressure demands are high.
Fuel Tank Level Remaining - Varies This parameter displays the amount of fuel remaining in the fuel tank as measured in liters or gallons. The control module determines the amount of fuel remaining in the tank by using information from the fuel level sensor(s). The scan tool will display a higher value with a full fuel tank, and a lower value with an empty fuel tank.
Fuel Temperature Sensor - Varies This parameter displays the current fuel temperature as calculated by the control module based on input from the fuel temperature sensor. The scan tool will display a higher value at higher fuel temperatures. The scan tool will display a lower value at lower fuel temperatures.
Fuel Transfer Pump Command - Varies with Fuel Level This parameter displays the commanded state of the fuel pump relay control circuit. The fuel pump relay should be ON when the scan tool indicates the fuel pump relay command is ON. The fuel pump relay should be OFF when the scan tool indicates the fuel pump relay command is OFF.
Fuel Used Since Last DPF Regeneration - Varies This parameter will display the amount of fuel used since last regeneration of the exhaust particulate filter.
GEN F-Terminal Signal - 0-100% This parameter indicates the generator field duty cycle as commanded by the voltage regulator or control module. The scan tool will display a higher value for a higher commanded generator output, and a lower value for a lower commanded generator output.
GEN L-Terminal Circuit Open Status - OK This parameter displays the diagnostic state of the Gen L-Terminal circuit. The scan tool will display OK, Incomplete, Short B+/Open, Short Gnd. The scan tool will display OK if the circuit is operating correctly.
GEN L-Terminal Command - 0-100% This parameter displays the control modules commanded state of the voltage regulator on the generator.
Glow Plug Command - OFF This parameter displays the voltage supply to the glow plugs as measured by the control module. The scan tool will display a higher value at high voltages, or a lower value at lower voltages.
High Idle Switch - Off This parameter displays the state of the high idle request input to the control module from the high idle switch. The scan tool will display ON or OFF. ON indicates the control module is receiving a request from the high idle switch to increase engine speed. OFF indicates the control module is not receiving a request from the high idle switch to increase engine speed.
IA Flow Valve Learned Closed Position - 0% This parameter displays Learned Closed Position of the IA flow valve.
IA Flow Valve Motor Command - 0% This parameter displays the duty cycle command by the control module for the IA Flow Valve.
IAF Valve Learned Minimum - 1% This parameter displays the learned value of the intake air flow valve. This value will be displayed in percent.
IAF Valve Position - 100% This parameter displays the actual position of the intake air flow valve.
IAF Valve Pos. Sensor - 4.27 Volts This parameter displays the voltage signal sent to the control module from the intake air valve. The intake air valve is a range of values indicating a high voltage when the throttle is closed to a low voltage when the throttle plate is fully open.
IAT Sensor 1 - Varies This parameter displays the temperature of the air entering the engine as calculated by the control module based on the input from the intake air temperature (IAT) sensor. The scan tool will display a low value when the air temperature is low, and a high value when the air temperature is high.
IAT Sensor 2 - Varies This parameter displays the temperature of the air entering the engine as calculated by the control module based on the input from the intake air temperature (IAT) sensor 2. The scan tool will display a low value when the air temperature is low, and a high value when the air temperature is high.
Ignition 1 Signal - Battery Voltage This parameter displays the voltage measured at the ignition 1 circuit of the control module. Voltage is applied to the control module when the ignition switch is in the ignition 1 position. The scan tool will display a low value when the voltage is low. The scan tool will display a high value, such as battery voltage, when the voltage is higher.
Ignition Accessory Signal - OFF This parameter displays the state of the ignition 0 input to the control module from the ignition switch. The scan tool will display On when the ignition switch is in the ignition accessory position. The scan tool will display Off when the ignition switch is in any other position.
Injection Pump Cam Reference Signal Missed - Counts This parameter will display the number of reference signals missed.
Injector Timing - Varies Indicates the current timing of the main injection pulse as calculated by the control module. The scan tool will display a higher value for a main injection event farther from top dead center (TDC). The Scan tool will display a lower value for a main injection event closer to TDC.
Intake Air Heater Command - Off This parameter displays duty cycle of the IAH as commanded by the control module.
%
MAF Sensor Engine Idling 9-20 g/s This parameter indicates the quantity calculated by the control module based on a signal from the MAF sensor. The scan tool will display a high value at high engine speeds, and a low value at low engine speeds.
Engine speed at 2,500 RPM 130-150 g/s
MAF Sensor - 2300-3100 Hz This parameter indicates the frequency signal received from the MAF sensor by the control module. The scan tool will display a high value at high engine speeds, and a low value at low engine speeds.
MAP Sensor - 0.95-1.06 Volts This parameter indicates the voltage signal received by the control module from the MAP sensor. The scan tool displays a low voltage at idle, and a high voltage at wide open throttle. Barometric pressure and altitude can effect these values.
Misfire Current Cyl. 1-8 - 0 This parameter displays the number of possible misfires during the last 200 cylinder firing events detected on Cylinders 1-8 as calculated by the control module. The misfires are calculated based on engine crankshaft rotation speed variations. The scan tool displays an incrementing counter. This counter should display some activity, but the activity should be the same for all cylinders.
Misfire Monitor Complete This Ignition - Varies This parameter displays the diagnostic monitor enable status during the current driving/monitoring cycle.
Misfire Monitor Enabled This Ignition - Varies This parameter displays the diagnostic monitor enable status during the current driving/monitoring cycle.
Particulate Filter Pressure Variance - Varies This parameter will display the pressure differential between the front and rear pressures at the DPF as calculated by the ECM. This will be displayed in kPa. As the DPF becomes restricted the differential pressure will increase.
Pilot Inj. Cyl 1-8 Command - On This parameter displays the commanded state of the fuel injectors for the pilot injection pulse as commanded by the ECM.
PNP Switch - Park/Neutral This parameter indicates the range selection of the automatic transmission as calculated by the control module based on input from the PNP switch. The scan tool will display, In Gear, Park, or Neutral depending on the PNP switch position.
PTO Active - No The scan tool will display Yes or No indicating the PTO is in operating function.
PTO Enable - No This parameter indicates all parameter have been met to enable the power take off (PTO), and the control module has determined that the power take off (PTO) is engaged.
PTO Engage Relay Command - Off This parameter displays the commanded state of the PTO relay control circuit. The scan tool will display ON or OFF. ON indicates the PTO relay control circuit is being grounded by the control module, allowing voltage to the load engage switch. OFF indicates the PTO relay is not being commanded on by the control module.
PTO Engine Shutdown - No This parameter displays the input status of the PTO engine shutdown switch to the control module. The scan tool will display YES or NO. Yes indicates the PTO engine shutdown switch is closed, grounding the engine shutoff signal circuit to the control module. OFF indicates the engine shutoff switch is open, allowing normal engine and PTO operation.
PTO Feedback Signal Relay - OFF This parameter displays the status of the PTO relay.
PTO Remote Start Request Signal - PTO Off The scan tool displays PTO Off, PTO On, Set 1, Set 2, No Action, Invalid, or Indeterminate. The PTO module monitors the signal circuit of the PTO remote switch.
Reduced Engine Power - Inactive This parameter will display the fuel system status as commanded by the ECM.
Regeneration Inhibition Reason - Varies This parameter displays the reason why a regeneration is not allowed.
Regeneration Status - Active, Not Required, or Complete This parameter displays the regeneration state.
Start Up ECT - Varies This parameter Indicates the engine coolant temperature at engine start up as calculated by the control module based on the signal from the ECT sensor. The scan tool will display a higher value on a warmer engine, and a lower value on a colder engine.
Start Up Fuel Temperature - Varies This parameter Indicates the fuel temperature at engine start up as calculated by the control module based on the signal from the fuel temperature sensor. The scan tool will display a higher value on a warmer fuel, and a lower value on a colder fuel.
Start Up IAT - Varies This parameter Indicates the intake air temperature at engine start up as calculated by the control module based on the signal from the IAT sensor. The scan tool will display a higher value during warmer under hood temperatures, and a lower value during colder under hood temperatures.
Start Up IAT Sensor 2 - Varies This parameter Indicates the intake air temperature at engine start up as calculated by the control module based on the signal from the IAT sensor 2. The scan tool will display a higher value during warmer under hood temperatures, and a lower value during colder under hood temperatures.
Starter Relay Command - Off The scan tool displays ON/OFF. The scan tool displays Off until the ignition is placed into the CRANK position, then it reads On.
TC Vane Pos. Ctrl. Solenoid - 1.0-1.5 amps This parameter displays the current draw of the vane position control solenoid through the control module. The scan tool will display a high current draw when the turbocharger vanes are being commanded closed. The scan tool will display a lower current draw when the turbocharger vanes are being commanded open.
TC Vane Position Lrn. Since DTC Clear - Yes This parameter indicates the status of the control module in learning the turbocharger vane position. The Scan tool will display Yes if the turbocharger vane position has been learned any time after the DTCs have been cleared. The scan tool will display No if the turbocharger vane position has not been learned since the last DTC clear. The control module will attempt to relearn during every ignition cycle. A relearn must be completed after any service on the turbocharger or control module.
TC Vane Position Lrn. This Run Cycle - Yes This parameter indicates the status of the control module in learning the turbocharger vane position. The Scan tool will display Yes if the turbocharger vane position has been learned this ignition cycle. The scan tool will display No if the turbocharger vane position has not been learned this ignition cycle. The control module will attempt to relearn during every ignition cycle. A relearn must be completed after any service on the turbocharger or control module.
TC Vane Pos. Ctrl. Solenoid - Varies This parameter displays the current commanded state of the turbocharger vane position control solenoid valve by the control module. The scan tool will display a higher value as the solenoid is commanded open. The scan tool will display a lower value as the solenoid is commanded closed.
TC Vane Position Learn Status - Yes This parameter indicates the status of the control module in learning the turbocharger vane position. The scan tool will display No if the turbocharger vane position has not been learned since the last DTC clear.
TC Vane Position Sensor - Varies This parameter displays the current commanded state of the turbocharger vane position control solenoid valve by the control module. The scan tool will display a higher value as the solenoid is commanded open. The scan tool will display a lower value as the solenoid is commanded closed.
TC Vane Position Sensor - Varies This parameter displays the voltage signal sent to the control module from the sensor. The scan tool will display a higher value as the solenoid is commanded open. The scan tool will display a lower value as the solenoid is commanded closed.
TCC/Cruise Brake Pedal Switch - - This parameter displays the state of the brake pedal as determined by the control module. The control module monitors the pedal switch on the brake pedal for vehicles equipped with an automatic transmission. The control module uses this information to release the torque convertor clutch when the brake pedal is applied. The scan tool will display Applied when the brake pedal is depressed. the scan tool will display Released when the brake pedal is not applied.
TCM MIL Request - Off This parameter indicates that a related transmission DTC set in the transmission control module (TCM) by displaying On/Off. The ECM turns ON the malfunction indicator lamp (MIL) when the TCM sends a message over the serial data circuit requesting MIL illumination.
Vehicle Speed Sensor - 0 km/mi This parameter indicates the vehicle speed as calculated by the control module based on a signal from the vehicle speed sensor (VSS). The scan tool will display a higher value at higher vehicle speeds, and a lower value at lower vehicle speeds.
VTD Auto. Learn Timer - Inactive This parameter indicates that either the auto learn timer (used in the auto learn procedure to enable VTD password learning) or the seed and key timer (used in the seed and key procedure to enable VTD password learning) is active.
H:M:S
VTD Fuel Disable - Inactive This parameter indicates the VTD system has disabled fuel.
VTD Fuel Disable Until Ign. Off - NO This parameter indicates the VTD system has disabled fuel for the remainder of the ignition cycle.
VTD Fuel Enabled - Active This parameter indicates the VTD system has enabled fuel.
VTD Password Learn Enabled - Yes This indicates learning of the VTD password received from the platform electronics is enabled. VTD password learning is first enabled in assembly plant (prior to the manufacturer's enable counter being set to zero) may be re-enabled using 1 of 2 procedures.
VTD Security Code Accepted - Yes This parameter displays if the theft deterrent code was accepted by the ECM.
VTD Security Code Lockout - Inactive This parameter displays if the VTD code is locked out of the ECM.
VTD Security Code Programmed - Inactive This parameter displays if the theft deterrent code is currently being programmed in the ECM.
VTD Security Info Programmed - Yes This parameter displays if the theft deterrent code has been programmed in the ECM.
VTD System Status - Standby This parameter displays the VTD system status in the BCM.
Wait to Start Indicator - Light OFF The wait to start indicator illuminates with the ignition ON and the engine OFF. The wait to start indicator will not illuminate during post-start glow plug operation.
Warm-ups Since DTC Cleared - Varies This parameter indicates the number of warm up cycles that have occurred Since DTCs were cleared. The scan tool will display a higher counts as more warm up cycles have occurred since the DTCs were cleared.
Warm-ups w/o Emission Faults - 0 This parameter indicates the number of warm up cycles that have occurred without an emission fault present. The scan tool will display a 0 if a fault has occurred. The scan tool will display a higher count if a number of warm up cycles have occurred without an emission fault.
Warm-ups w/o Non-emission Faults - 0 This parameter indicates the number of warm up cycles that have occurred without a non-emission fault present. The scan tool will display a 0 if a fault has occurred. The scan tool will display a higher count if a number of warm up cycles have occurred without a non-emission fault.
Water in Fuel Sensor - No Water This parameter will display Water if fuel is present in the fuel or No Water when water is no longer present in the fuel.
Output Control

Parameter Description
A/C Relay The engine must be running and the ECM must receive an A/C request from the HVAC control module in order to enable the output control. The ECM de-energizes the A/C compressor clutch relay when you select OFF. The relay remains de-energized until you select ON.
Balance Rate Monitor This function will allow actual balance rate values to be displayed.
Cooling Fan The percent of engine cooling fan requested from the ECM.
Cylinder Power Balance Disables each fuel injector. Device Control can be changed at any engine or vehicle speed. The device control will not change unless changed or cancelled by the scan tool.
Dash Lamps Malfunction Indicator Lamp-Activates the malfunction indicator lamp (MIL). The MIL will remain illuminated until cancelled by the scan tool.
DPF Regeneration Indicator This function will activate the Clean Exhaust Filter message or green indicator lamp and will remain ON until it is cancelled with the scan tool.
DPF Regeneration Enable This function enables a DPF Regen when the vehicle meets the conditions for running. This function will by-pass the normal soot model, so the next time the vehicle is under the conditions for an active regeneration to take place, the ECM will go ahead and initiate the regeneration event.
DPF Reset Replace DPF Resets all DPF parameters to zero.
DPF Service Regeneration This function enables a DPF Regen. The engine coolant must be greater than 70-115°C (158-239°F). Vehicle must be in Park. Ambient temperature must be greater than -30°C (-22°F). Brake pedal and accelerator must be in the released position. The scan tool will display all inhibit reasons. The scan tool must remain connected until test is complete. This function takes approximately 35 minutes to complete. During this procedure the RPM will slowly increase to 2,500 RPM and remain there for approximately 25 minutes.
EGR Solenoid Activates the exhaust gas recirculation (EGR) solenoid ON or OFF. The EGR position is limited to 40 percent duty cycle, which is 100 percent commanded open valve. The device control is limited to 10 seconds ON, with a 10 second OFF cooling time. This device control is disabled by DTC P0403.
Engine Speed Control Adjusts the engine speed in 25, 100, or 500 RPM increments between 600-1500 RPM. The Device Control will not change unless changed or cancelled by the scan tool.
Engine Shutdown The scan tool displays On or Off. This is the state of the engine shutdown indicator as commanded by the IPC.
Fuel Injector Balance Procedure Disables each fuel injector injection. Device Control can be changed at any engine or vehicle speed. The device control will not change unless changed or cancelled by the scan tool.
Fuel Pressure Control This parameter displays the fuel rail pressure regulator duty cycle as commanded by the control module. The scan tool will display a lower value for a higher commanded fuel pressure, and a higher value for a lower commanded fuel pressure.
Fuel Pump Activates the fuel transfer pump or prime pump (depending on application) ON or OFF. The Device Control will not change unless changed or cancelled by the scan tool.
Fuel Transfer Pump Relay This function commands the fuel transfer pump relay ON/OFF.
GEN-L Terminal The commanded states are ON and OFF. Selecting OFF commands the ECM to turn OFF the generator and stop generating an output voltage.
IAF Valve Motor This function increases or decreases the position of the IAF valve.
IAF Valve Position This parameter displays the actual position of the intake air flow valve.
Pilot Injector Balance Procedure Disables each fuel injector pilot injection. Device Control can be changed at any engine or vehicle speed. The device control will not change unless changed or cancelled by the scan tool.
TC Vane Position Sensor Adjusts the turbocharger vane position in 5 percent increments from 0-100 percent. The device control will be aborted if engine speed is above idle or if the coolant temperature is too cold.
TC Vane Solenoid Cycles the turbocharger vane position solenoid to 100 percent boost and back to 0 percent boost. The device control is limited to engine speeds less than 1,500 RPM and will be disabled if DTC P0047 or P0048 are set.
Wait to Start The scan tool displays On or Off. This is the state of the wait to start indicator as commanded by the PCM.