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Home >> GMC >> 1994 >> Forward Control 7.4 N >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 6.5L Diesel >> Self-Diagnostic System >> Typical Tech-1 Data Values
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Typical Tech-1 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. For additional information, see tester owner's manual.
TYPICAL TECH-1 DATA VALUES

Tester Position Units Measured Nominal Data Value
A/C Clutch On/Off Off
Accel Ped Pos No. 1 Volts .35-.95
Accel Ped Pos No. 2 Volts 4.0-4.5
Accel Ped Pos No. 3 Volts 3.6-4.0
BARO kPa/Volt 70-100/3.5-4.5 (Varies With Altitude)
Calibration ID 0-9999 Internal
Cam Ref Missed Counts 0
C/C Brake Switch Opn/Clsd Open
Crank Ref Missed Counts 0
Cruise Control On/Off Off
Desired Idle RPM PCM Commanded (Based On Temp)
Desired Inj Tim # Of ° Varies
EGR Duty Cycle % 50-100 (May Vary)
EGR Pressure kPa/Volt 50-100/2.8-3.0 (Varies)
Engine Cool Temp °F/°C 185-221 (85-105)
Engine Shut Off On/Off On
Engine Speed RPM +/-100 From Desired
Fuel Rate Mm 0-40 (Varies W/Engine Load)
Fuel Temperature °F/°C 70-110 (21-43)
Glow Plug Relay Volts 12.0-14.5
Glow Plug Volts Volts 12.0-14.5
Inj Pulse Width Mil./Sec 1.7-1.9 (May Vary)
Intake Air Temp °F/°C 50-194 (10-87) (Depends On Underhood Temp)
Measured Inj Tim # Of ° Varies
System Voltage Volts 12.0-14.5
TCC Brake Switch Clsd/Opn Closed
TCC Solenoid On/Off Off
TDC Offset # Of ° 0-2.02 (Varies)
Throttle Angle % 0
Time From Start Hrs/Min/Sec Varies
Trans Range Sw Invalid, Rev, D4, D3, D2, Lo, P/N Park/Neut
1-2 Sol/2-3 Sol On/Off On/On
4WD Low Switch On/Off Off