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Scan Tester - Test Data Parameters

NOTE: Information in the following table is a typical reading taken on vehicle with engine idling, upper radiator hose hot, closed throttle, transmission in Park or Neutral, "closed loop" status achieved and all accessories off (except as noted in tables). Data parameters are updated every 1 1/4 seconds. On systems using P-4 computers, parameter updates are virtually instantaneous. Not all devices & systems are used on all models.
FULL FUNCTION (CARBURETED)

Tester Position Units Measured Nominal Data Value
A/C Clutch On/Off Off (On with A/C)
A/C Low Freon Switch On/Off On when freon low
A/C Request Yes/No No/Yes(with request)
AIR Divert Solenoid On/Off On (air to switching sol.)
AIR Divert Solenoid On/Off Off (air to atmosphere)
AIR Switching Solenoid On/Off On (to exhaust manifold)
AIR Switching Solenoid On/Off Off (to catalytic converter)
BARO Volts 3-4.5
Battery Voltage Volts 13.5-14.5
Canister Purge Sol. On/Off On cold engine (idle some)
Coolant Fan On/Off Off below 216°F (102° C)
Coolant Temp °C 85-105° (norm. temp.)
Cross Counts Counts 0-255
EFE Sol./Relay On/Off On below 85°C
EGR Solenoid On/Off On when energized
EGR Duty Cycle 0-100% 0/closed-100/fully open
Ignition/Crank On/Off On with ignition/crank
ILC Solenoid On/Off On extended/Off retracted
ISC Motor On/Off On controls idle
ISC Motor On/Off Off = no control
Knock Retard (ESC) Counts 0-255
Knock Signal Yes/No Yes when knock exists
MAP Volts 1 (idle) to 4.5 (WOT)
M/C Dwell Degrees 10-50° varying
Nose Switch On/Off On when depressed
O2 Sensor Millivolts 100 (lean) to 999 (rich)
Open/Closed Loop Status Ol/Cl Closed/Open during extended idle
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 (auto.)
RPM RPM Spec. +/- 50 RPM Neut. (man.)
Spark Advance # of Deg Varies
TCC On/Off Off (On with command)
Throttle Angle 0-100% 0
Throttle Kicker On/Off On with A/C & deceleration
TPS Volts .5 (closed) to 5.0 (WOT.)
Trouble Codes Code # No Codes
Turbo Boost On/Off On when activated
VAC Volts 4.5 (idle) to 1 (WOT)
VSS or MPH MPH 0-actual
WOT Switch On/Off On at WOT
3rd Gear Switch On/Off On/3rd & 4th gear
4th Gear Switch On/Off On/4th gear