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Engine Control Module Scan Tool Information (2.0L Diesel)

The Engine Control Module Scan Tool Data List contains all engine-related parameters that are available on the scan tool. This is a master list arranged in alphabetical order and not all the parameters listed are in every engine platform.

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
5 Volt Reference 1, Reference 2, or Reference 3 Ignition ON OK This parameter displays the output voltage from the 5-volt reference circuit to the control module.
A/C Disengage Reason A/C OFF Invalid This parameter displays the A/C compressor disengage reason. There are 8 different possible faults for the A/C compressor to disengage.
A/C Refrigerant Pressure A/C OFF 0-5 Volts This parameter displays the voltage from the A/C high side pressure sensor signal circuit to the control module.
A/C ON 0-5 Volts
A/C Refrigerant Pressure A/C OFF 700-900 kPa (101-130 psi) This parameter displays the pressure from the A/C high side pressure sensor signal circuit to the control module.
A/C ON 900-1300 kPa (130-174 psi)
A/C Relay Command A/C ON On This parameter displays the state of the air conditioning (A/C) clutch relay control circuit as commanded by the control module.
A/C Request Signal A/C ON Yes This parameter displays the state of the A/C request input to the control module from the heating, ventilation, and air conditioning (HVAC) controls.
Alternator L Terminal - ON This parameter displays whether the control module is allowing the generator to operate.
Ambient Air Temperature Calculated - Varies This parameter displays the calculated ambient air temperature.
APP at Idle - Yes This parameter displays the angle of the accelerator pedal position (APP) as calculated by the control module using the signals from the APP sensors.
APP Sensor 1 or 2 - APP 1-1.02 Volts
APP 2-0.51 Volts
This parameter displays the voltage of each APP sensor signal circuit as measured by the control module.
APP Sensor 1 or 2 Indicated - APP 1-0%
APP 2-0%
This parameter displays the percent of each APP sensor signal circuit as measured by the control module.
APP Sensors - 0% This parameter displays the angle of accelerator pedal position as calculated by the control module using the signals from the APP sensors.
Auto Learn Counter - 0 Counts This parameter displays the status of the theft deterrent system password learn.
Aux Htr. Relay 1 Command - OFF This parameter displays the commanded state of the aux heater relay 1 control circuit.
Aux Htr. Relay 2 and 3 Command - OFF This parameter displays the commanded state of the aux heater relay 2 and 3 control circuit.
Aux Heater Request - OFF This parameter displays the requested state of the aux heater.
BARO - 65-104 kPa (8-16 psi) - Varies with altitude This parameter displays the barometric pressure. The control module uses the barometric pressure sensor input for fuel control to compensate for altitude differences.
BARO - 0-5 Volts - Varies with altitude This parameter displays the barometric pressure in voltage. The control module uses the barometric pressure sensor input for fuel control to compensate for altitude differences.
Battery Voltage Ignition ON B+ This parameter displays the voltage measured at the battery circuit of the control module.
Boost Pressure Sensor - 82-110 kPa (12-16 PSI) This parameter displays the turbocharger boost pressure inside the engine as calculated by the control module based on the signal from the Boost pressure sensor.
Boost Pressure Sensor - 1.45-1.75 Volts This parameter displays the voltage of the turbocharger boost pressure inside the engine calculated by the control module based on the signal from the Boost pressure sensor.
Calculated Mass Air Flow - 630-690 g/s This parameter displays the calculated air flow into the engine. The calculation is used in several diagnostics to determine when to run the diagnostics.
Clutch Pedal Switch - Applied This parameter displays the current state of the clutch pedal as determined by the control module. The control module monitors the pedal switch on the clutch pedal for vehicles equipped with a manual transmission.
Cruise Control Active Cruise Control ON Yes This parameter displays the status of the cruise control system as determined by the control module.
Cruise Disengage 1-6 History - Reason This parameter displays the history of the action taking with the cruise system.
Cruise ON/OFF Switch Cruise Control ON Yes This parameter displays the state of the cruise ON/OFF switch input to the control module.
Cruise Release Brake Pedal Switch - Released 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.
Cruise Resume/Accel. Switch Cruise Resume/Accel. Switch ON On This parameter displays the state of the cruise Resume/Accel switch input to the control module from the cruise control system.
Cruise Set/Coast Switch Cruise Set/Coast Switch ON On This parameter displays the state of the cruise Set/Coast switch input to the control module from the cruise control system.
Cylinder Air - 240.00-280.00 mg/stk This parameter displays the actual amount of cylinder air.
Desired Boost - 98 kPa This parameter displays the desired turbocharger boost pressure inside the engine as calculated by the control module based on the signal from the Boost pressure sensor.
Desired Cylinder Air - 240.00-280.00 mg/stk This parameter displays the difference between the actual amount of cylinder air and the desired amount of cylinder air.
Desired Fuel Rail Pressure - 42500.0-44500.0 kPa
6215.0-6265.0 psi
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.
Desired Idle Speed - 700-800 RPM This parameter displays the desired engine idle speed as commanded by the control module.
Distance Since DPF Indicator ON without Regeneration - Varies This parameter displays the mileage that has elapsed since the diesel particulate filter indicator was illuminated without a regeneration occurrence.
Distance Since Last DPF Regeneration - Varies This parameter displays the mileage that has elapsed since the last diesel particulate filter regeneration has occurred.
DPF Flow Calculated - 24600-27000 Liters/Hours The parameter displays the calculated flow of DPF.
DPF Indicator Command - OFF This parameter displays the commanded state of the dpf indicator lamp control circuit.
DPF Regen Command - 0 Counts The parameter displays the DPF regeneration command.
DPF Regen Flow Resistance - 0.000 pa/m3 /h
0.000 psi/cfm
This parameter displays the difference between the front and rear pressures at the DPF as calculated by the ECM.
DPF Regeneration Inhibit - No The parameter displays if the DPF regeneration was inhibited.
DPF Regen Interrupted - No The parameter displays if the DPF regeneration was interrupted.
DPF Soot Mass - 2g-8g This parameter displays the amount of calculated soot in exhaust particulate filter.
ECM Authentication Status Ignition ON Valid This parameter displays the status of the control module this ignition cycle. The scan tool will display valid when an internal control module reset has occurred this ignition cycle. The scan tool will display invalid when no internal control module reset has occurred this ignition cycle.
ECM Challenge Status Ignition ON Invalid This parameter displays the status of the control module this ignition cycle. The scan tool will display valid when an internal control module reset has occurred this ignition cycle. The scan tool will display invalid when no internal control module reset has occurred this ignition cycle.
ECM Response Source Ignition ON Normal This parameter displays the status of the control module response this ignition cycle.
ECT Sensor - -39 to +140°C ( -38 to +284°F) This parameter displays the temperature of the engine coolant based on input to the control module from the engine coolant temperature (ECT) sensor.
ECT Sensor - 0-5 Volts This parameter displays the voltage calculated by the control module from the engine coolant temperature (ECT) sensor.
EGR Position Command - 40-55% This parameter displays the percent of the duty cycle commanded by the control module.
EGR Solenoid Command - 40-55% This parameter displays the percent of the EGR solenoid commanded by the control module.
EGR Solenoid Command - OFF This parameter displays the state of the control circuit for EGR solenoid as commanded by the control module.
EGT Sensor 1 or 2 - EGT 1 - +110°C to +140°C ( +230°F to +284°F)
EGT 2 - +80°C to +120°C ( +176°F to +248°F)
This parameter displays the temperature of the exhaust gas calculated by the control module based on the input from the exhaust gas temperature sensors.
EGT Sensor 1 or 2 - EGT 1 - 1.00-1.15 Volts
EGT 2 - 0.90-1.10 Volts
This parameter displays the voltage calculated by the control module based on the input from the exhaust gas temperature sensors.
Engine Load Engine Idling 20-35% This parameter displays the percent of the calculated engine load based on inputs to the control module from various engine sensors.
Engine speed at 2,500 RPM 15-25%
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.
Engine Oil Pressure Switch - OK This parameter displays the pressure of the engine oil calculated by the control module using a signal from the engine oil pressure (EOP) sensor.
Engine Run Time Engine Operating 0:00:00
Increments when the engine is operating
This parameter displays the time elapsed since the engine was started.
Engine Speed Engine Cranking Greater than 60 RPM This parameter displays the speed of the engine crankshaft rotation from information received from the crankshaft position (CKP) sensor. If there is a CKP sensor DTC, the ECM calculates the engine speed from one of the camshaft position (CMP) sensors.
Engine Idling Approximately 750-850 RPM
Fan Control 1, Control 2, or Control 3 Command Fans Commanded ON On This parameter displays the control module commanded state of the fan relay control circuits.
Fuel Heater Command - OFF This parameter displays the control module commanded state of the fuel heater control circuit.
Fuel Level Sensor - 0-100% This parameter displays the percent of fuel in the fuel tank calculated by the control module.
Fuel Level Sensor Left Tank or Fuel Level Sensor Right Tank - 0-5 Volts This parameter displays the voltage received by the control module from the sensor used to monitor the fuel level inside the fuel tanks.
Fuel Pressure Regulator 1 - 1300-1400 mA This parameter displays the control modules commanded state of the fuel rail pressure regulator 1.
Fuel Pressure Regulator 2 - 500-600 mA This parameter displays the control modules commanded state of the fuel rail pressure regulator 2.
Fuel Pressure Regulator 2 Command - 20% This parameter displays the percent of the fuel rail pressure regulator duty cycle commanded by the control module.
Fuel Pump Command - 34% This parameter displays the percent of the control modules commanded state of the fuel pump.
Fuel Pump Relay Command Ignition ON, engine OFF Fuel pump on for 2 seconds This parameter displays the control modules commanded state of the fuel pump relay control circuit.
Engine idling On
Fuel Rail Pressure Sensor - 42800-43800 kPa
(6207-6352 PSI)
This parameter displays the fuel rail pressure calculated by the control module using the signal from the fuel rail pressure (FRP) sensor.
Fuel Rail Pressure Sensor - 1.40-1.50 Volts This parameter displays the voltage of the fuel rail pressure calculated by the control module using the signal from the fuel rail pressure (FRP) sensor.
Fuel Temperature Sensor - +25°C to +40°C ( +77°F to +104°F) This parameter displays the fuel temperature calculated by the control module based on input from the fuel temperature sensor.
Fuel Temperature Sensor - 2.80 Volts This parameter displays the voltage calculated by the control module based on input from the fuel temperature sensor.
Gen F Terminal Signal - 25-35% This parameter displays the commanded state of the generator by the control module.
Glow Plug - 0% This parameter displays the percent of the voltage supply to the glow plugs as measured by the control module.
Glow Plug Command - OFF This parameter displays the control module commanded state of the glow plug.
Glow Plug Lamp Command - OFF This parameter displays the commanded state of the glow plug lamp circuit by the control module.
IA Flow Valve Motor Command - 55-65% This parameter displays the percent of the control modules commanded state of the intake air flow valve.
IAT Sensor 1 or Sensor 2 - -39 to +140°C ( -38 to +284°F) This parameter displays the temperature of the air entering the engine air duct calculated by the control module based on the input from the intake air temperature sensors.
Ignition 0 Ignition ON Active This parameter displays the voltage measured at the ignition 0 circuit of the control module. Voltage is applied to the control module when the ignition switch is in the ignition 0 position.
Ignition 1 Ignition ON Active 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.
Immobilizer Programmed - Yes This parameter indicates the status of the immobilizer system. The scan tool will display YES if the immobilizer system is ready to be programmed.
Immobilizer State - Release This parameter indicates the status of the immobilizer system.
MAF Sensor - On This parameter indicates the quantity calculated by the control module based on a signal from the mass air flow (MAF) Sensor.
Main Injection Fuel Ratio - 6.5 mm3 This parameter displays the air to fuel ratio based on the oxygen sensor inputs. The ECM uses the fuel trims to adjust fueling in order to attempt to maintain a certain air fuel ratio.
Main Injection Timing - On This parameter displays the current timing of the main injection pulse as calculated by the control module.
MAP Sensor - 95-104 kPa This parameter indicates the manifold absolute pressure inside the engine as calculated by the control module based on the signal from the manifold absolute pressure (MAP) sensor.
MIL Command - Off This parameter displays the commanded state of the malfunction indicator lamp (MIL) control circuit by the control module.
Particulate Filter Pressure Variance - Varies This parameter displays the percent calculated by the control module, based on the input from the exhaust gas temperature sensors when the particulate filter is full and needs a particulate filter regeneration.
Particulate Filter Pressure Variance - 0.40-0.60 Volts This parameter displays the voltage calculated by the control module, based on the input from the exhaust gas temperature sensors when the particulate filter is full and needs a particulate filter regeneration.
Pilot Injection Trim Average - 10-36 microseconds This parameter displays the average commanded on time of the fuel injectors for the pilot injection pulse.
Pilot Injection Cyls. 1-4 - 360-380 microseconds This parameter displays the commanded on time of the fuel injectors for the pilot injection pulse. The scan tool will display a higher value for a longer injection pulse.
PNP Switch - Park/Neutral This parameter displays whether the transmission range selector is in park/neutral or in gear.
Security Code Programmed - No This parameter indicates the status of the security system.
Starter Relay Command - Off This parameter displays the commanded state of the starter relay.
Stoplamp Pedal Switch - Released This parameter displays the state of the brake pedal as determined by the stop lamp pedal switch.
TCC Vane Pos. Ctrl. Solenoid TCC Enable Solenoid Command ON 80% This parameter displays the percent of the vane position control solenoid from the control module.
Throttle Position - 55-70% This parameter displays the percent of throttle opening as calculated by the control module using information from the TP sensor.
Vehicle Speed - 0 Km/h
0 mph
This parameter displays the speed of the vehicle as calculated by the transmission control module (TCM) from information received from the vehicle speed sensor (VSS).
VTD Password Learn Enabled Ignition ON No This parameter indicates the status of the theft deterrent system password learn.
VTD Security Code Accepted Ignition ON No This parameter indicates the status of the theft deterrent system security code.
VTD Security Code Lockout Ignition ON Active This parameter Indicates if the theft deterrent system is disabling fuel delivery.
Water In Fuel Sensor - Off This parameter displays the commanded state of the water in fuel lamp by the control module.
Engine Control Module (ECM) Scan Tool Output Controls

Output Control Description
A/C Relay
IMPORTANT: The A/C Relay Command parameter may not change states when using this output control.
This function activates the A/C compressor relay. The normal commanded state of the A/C relay is OFF. The A/C compressor will turn ON/OFF when commanded ON/OFF. The system remains in the commanded state for approximately 5 seconds. The engine control module (ECM) will inhibit the operation of the A/C relay when the ambient air temperature is low.
Alternator Lamp This function activates the alternator lamp. The glow plug indicator lamp will remain illuminated until cancelled by the scan tool.
Aux Heater Relay 1
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function controls the aux heater relay 1.
Aux Heater Relay 2 & 3
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function controls the aux heater relays 2 and 3.
Cranking Speed Test
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function enables the ECM to detect engine speed of each cylinder without activating the fuel injectors.
Cruise Lamp This function activates the cruise control lamp. The cruise control indicator lamp will remain illuminated until cancelled by the scan tool.
DPF Indicator This function activates the DPF lamp. The DPF indicator lamp will remain illuminated until cancelled by the scan tool.
DPF Reset Replace DPF
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function resets the learned values for the diesel particulate filter in the ECM after the DPF has been replaced.
DPF Reset Replace ECM
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function resets the learned values for the diesel particulate filter in the ECM after the ECM has been replaced.
DPF Reset Replace Injectors
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function resets the learned values for the diesel particulate filter in the ECM after one or more injectors have been replaced.
DPF Reset Replace Pressure Sensor
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function resets the learned values for the diesel particulate filter in the ECM after the DPF pressure sensor has been replaced.
EGR Solenoid This function opens or closes the exhaust gas recirculation (EGR) solenoid. The EGR solenoid increases or decreases in 10 percent increments. The device control will not change unless changed or cancelled by the scan tool.
Engine High Temp. Lamp This function activates the engine high temperature lamp. The engine high temperature lamp will remain illuminated until cancelled by the scan tool.
Fan Relay 1 This function controls the low speed cooling fan relay. When commanded ON, the cooling fan will turn ON at low speed for approximately 5 seconds.
Fan Relays 2 & 3 This function controls the high speed cooling fan relay. When commanded ON, the cooling fan will turn ON at high speed.
Fan Relays 1, 2 & 3 This function controls the high speed cooling fan relay. When commanded ON, the cooling fan will turn ON at high speed.
Fuel Heater This function activates the fuel heater relay ON or OFF. The Device Control will not change unless changed or cancelled by the scan tool.
Fuel Pump
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function 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 Quantity Test
IMPORTANT: This function is only allowed with the engine idling.
This function enables the engine control module (ECM) to detect the fuel quantity in each cylinder.
Fuel Trim Reset This function resets the fuel trim data in all fuel trim cells.
Gen L-Terminal
IMPORTANT: This function is only allowed with the engine idling.
This function controls the system voltage. When commanded ON, normal system voltage output is present. When commanded OFF, system voltage output is no longer present, Ignition 1 signal continues to drop, Gen L-Terminal goes to OFF and Gen F-Terminal continues to drop.
Glow Plug This function activates the Glow Plug Controller ON or OFF. The Device Control will be aborted after 12 seconds for the first activation, and after 5 seconds for every other activation. The Device Control is inhibited if the engine is running.
Glow Plug Lamp This function activates the glow plug indicator lamp. The glow plug indicator lamp will remain illuminated until cancelled by the scan tool.
Idle Speed Control
IMPORTANT: This function is only allowed with the engine idling.
This function 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.
Idle Speed Test
IMPORTANT: This function is only allowed with the engine idling.
This function enables the ECM to detect engine speed of each cylinder without making any fuel correction.
Malfunction Indicator Lamp This function activates the malfunction indicator lamp (MIL). The MIL will remain illuminated until cancelled by the scan tool.
Oil Life Reset This function turns OFF the change oil lamp and resets the values in the ECM.
Reset Injection Value - All Cyl.
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function resets the learned values in the ECM after all the fuel injectors have been replaced.
Reset Injection Value - Cyl. 1
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function resets the learned values in the ECM after cylinder 1 fuel injector has been replaced.
Reset Injection Value - Cyl. 2
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function resets the learned values in the ECM after cylinder 2 fuel injector has been replaced.
Reset Injection Value - Cyl. 3
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function resets the learned values in the ECM after cylinder 3 fuel injector has been replaced.
Reset Injection Value - Cyl. 4
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function resets the learned values in the ECM after cylinder 4 fuel injector has been replaced.
Reset Injection Value - ECM
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function resets the learned fuel injector values in the ECM after the ECM has been replaced.
Throttle Blade Control
IMPORTANT: This function is only allowed with the ignition ON, engine OFF.
This function opens or closes the throttle blade. The throttle blade increases or decreases in 10 percent increments. The scan tool initiates the test when the following conditions are met:
  • There are no vehicle speed sensor DTCs set.
  • The vehicle speed is 0 km/h (0 mph).
  • The ignition is ON, with the engine OFF.
  • The ECM is not commanding a throttle learn.
The system remains in the commanded state until cancelled by the scan tool.
TCC Vane Pos. Cntl. Solenoid
IMPORTANT: This function is only allowed with the engine idling.
Cycles the turbocharger vane position solenoid to 95 percent boost and back to 0 percent boost. The device control is limited to engine speeds less than 2,000 RPM.