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Home >> GMC >> 1995 >> Forward Control 7.4 N >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 5.7L >> Self-Diagnostic System >> Scan Tester Data
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Scan Tester Data

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.
SCAN TESTER DATA

Tester Position Units Measured Nominal Value
A/C Clutch On/Off Off (On With A/C)
A/C Request Yes/No No/Yes (With Request)
Battery Voltage Volts 13.5-14.5
Clear Flood On/Off See Tester Manual
Coolant Temp. °C 85-105° (Norm. Temp.)
Crank RPM RPM 100-900
Cross Counts Counts 0-255
Desired RPM RPM ECM Desired RPM
EGR Actual 0-100% 0/Closed-100/Fully Open
EGR Desired 0-100% 0/Closed-100/Fully Open
EGR Duty Cycle 0-100% 0/Closed-100/Fully Open
Fuel Trim Cell Cell# 0
Fuel Trim Enable Yes/No No
Fuel Trim LT Counts 118-138 (128 Normal)
Fuel Trim ST Counts 110-145 (128 Normal)
IAC Counts 0-50
IAT °C 10-90°
Injector Pulse Width Mil./Sec .8-3.0
KS Retard Deg. 12
Knock Signal Yes/No Yes When Knock Exists
MAP Volts 1 (idle) To 4.5 (WOT)
Open/Closed Loop Status Ol/Cl Closed/Open During Extended Idle
Oxygen Sensor Millivolts 100 (Lean) To 999 (Rich)
P/N Switch P/N/RDL Park/Neutral
P/S Switch Norm/Hi Normal
PROM I.D. PROM # Original Factory Number
RPM RPM Spec. +/-25 RPM Drive (A/T); Spec. +/-50 RPM Neut. (M/T)
Spark Advance Degrees 0-20
TCC On/Off Off (On With Command)
TPS Volts .45 (Idle) To 5.0 (WOT)
Throttle Angle 0-100% 0 (Idle) To 100 (WOT)
Trouble Codes Code # No codes
Upshift Light (M/T) On/Off Off
VSS Or MPH MPH 0-Actual