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Home >> GMC >> 1998 >> Forward Control 6.5 F >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 6.5L Turbo Diesel >> Self-Diagnostic System >> Typical Tech 1 Or 2 Data Values
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Typical Tech 1 Or 2 Data Values

NOTE: Information contained in the following table is typical of readings taken on vehicle with engine idling, upper radiator hose hot, throttle closed, transmission in Park or Neutral, closed loop status achieved and all accessories off (except as noted in tables). Not all devices and systems are used on all models. Refer to scan tool manufacturer's instructions.
TYPICAL TECH 1 OR 2 DATA VALUES

Tool Position Units Measured Nominal Data Value
A/B/C Range Sw. On, On, On/Off, Off, Off On/Off/On
Glow Plug System Disabled/Enabled Enabled (Key On)
A/C Compressor Engage/Disengage Disengage
A/C Relay On/Off Off
A/C Request On/Off Off
Actual EGR kPa 80-104
Actual Injector Timing Degrees 4-10@Idle 14-20@2500 RPM
APP Angle % 0@Idle 4-8@2500 RPM
APP 1 Volts .44-.95@Idle .8-1.3@2500 RPM
APP 2 Volts 3.9-4.5@Idle 3.7-4.3@2500 RPM
APP 3 Volts 3.6-4.1@Idle 3.5-4.0@2500 RPM
BARO kPa 65-104 (Varies W/Alt.)
Boost Pressure kPa 60-170 (All RPMs)
Brake Switch Opn/Clsd Open
Calc. A/C Load Count 0
Crank Ref. Missed Counts 0 (Missed)
Cruise Active On/Off Off
Cruise Brake Sw. Opn/Clsd Closed
Cruise Switch On/Off Off
Cylinder Air g/cyl 0.3-1.0 (All RPMs)
Desired Cyl. Air g/cyl 0.3-1.0 (All RPMs)
Desired EGR kPa 80-104
Desired Idle RPM 630-650
Desired Injector Timing Degrees 4-7@Idle 14-20@2500 RPM
Desired Injector Timing (1) Degrees 4-10
DTC Set This Ign. Counts 0
ECT °F/°C 185-221 (85-105) (Varies With Temp.)
ECT Sensor Volts 2.0-3.0 (Varies With Temp.)
EGR Adap. Learn Counts 0
EGR Duty Cycle kPa 0 (All RPMs)
EGR Sensor Volts 4.6-4.9 (All RPMs)
EGR Vent Sol. On/Off Off
Engine Load % 1-5
Engine Load (1) % 4-8
Engine Run Time Hr/Min/Sec Varies With Eng. Run Times
Engine Speed RPM +/-100 From Desired
Engine Torque Ft Lbs 3-8
Engine Torque (1) Ft Lbs 7-10
ESO Solenoid On/Off On
Fuel Rate mm(3) 7-15 (All RPMs)
Fuel Temperature °F/°C 50-194 (10-90)
Glow Plug Volts 0
Glow Plug System Disabled/Enabled Enabled (Key On)
IAT °F/°C 50-194 (10-90) (Varies With Temp. & Load)
IAT Sensor °F/°C 50-194 (10-90)
Ignition Volts Volts 12-14
Injector Pump Cam Ref. Missed Counts 0
Injector Pump Sol. Closure Time Milsec 1.7-1.9 (All RPMs)
Lift Pump Volts 12-16
Lift Pump System Disabled/Enabled Enabled
MAF gms/s 20-35@Idle 120-140 @ 2500 RPM
MAF Frequency Hz 4000-4500@Idle 7200-7800 @ 2500 RPM
MIL Light On/Off Off
MPH/KPH MPH/KPH 0-0
No. Of DTCs Counts 0
PCM In VTD Fail Enable Yes/No No
Resume Switch On/Off Off
Set Switch On/Off Off
Start-Up ECT °F/°C Varies (Depends On Start-Up ECT)
Start-Up ACT °F/°C Varies
STS Light On/Off Off
TDC Offset Degrees +.75 To -1.75
TFT Sensor Volts 1.8-2.2
TR Switch P/N, R, D1, D2, D3 Park/Neutral
Trans. Fluid Temp. °F/°C 122-158 (50-70)
Wastegate Sol. % 50-70@Idle 20-40@2500 RPM
Wastegate Sol. (1) % 50-70
Vehicle Speed MPH/KPH 0
VTD Auto Learn Timer Active/Inactive Inactive
VTD Fuel Disable Active/Inactive Inactive
VTD Fuel Disable Until Ign. Off Yes/No No
1-2 Solenoid On/Off On
2-3 Solenoid On/Off Off
# Of Curr DTCs Counts 0
(1) P-Van.