Scan Tool Data List

The "SCAN" data values, listed below, are typical for the test parameters of a "TECH-1" or equivalent "scan" tool connected to the ALDL diagnostic connector, and under the following conditions:

Engine running at idle/closed throttle.
Engine at normal operating temperature.
System operating in "closed-loop".
Accessories "OFF".
Brake NOT applied.

Many of the parameters show "data" rather than voltage or resistance values, and cannot be read using a volt/ohm meter.


PARAMETER UNITS TYPICAL VALUE

Engine Speed RPM ± 100 RPM from desired idle
Desired Idle RPM varies w/temperature
Coolant Temp °C°F Varies 85-109°C (185-223°F)
Intake Air Temp °C°F Varies 10-80°C (50-176°F)
MAP kPa/Volts 29 - 48 kPa (1-2 volts)
BARO kPa/Volts 58 - 114 kPa (2.5-5.5) volts depending on altitude and barometric pressure
Throttle Position Volts 0.29 - 0.98
Throttle Angle Percent (%) 0%
Heated Oxygen (HO2S) Millivolts (mV) Varies (100-1000)
Injector Pulse Width M/sec (milliseconds) 3 - 6 and varying
Spark Advance Degrees Advance 18-24° (varies)
Spark Retard Degrees Timing Retard 0°
S. T. Fuel Trim Counts varies
L. T. Fuel Trim Counts 110 - 150
Open/Closed Loop Open/Closed Loop Closed Loop
Fuel Trim Cell Cell # 16 (idling in Park or Neutral)
Fuel Trim Inable No/Yes Yes
Knock Signal Yes/No No
EGR 1/EGR 2/EGR 3 On/Off Off
Idle Air Control Counts 5 - 50
Park/Neutral P-N/R-DL P-N
Vehicle Speed mph/kph 0 0
Fuel Evap Purge 0-100% 0%
Shift light On/Off Off
Ign Control 24X Sig RPM +/- 100 RPM in N from desired
Ign Control CAM Sig 0/1 Varies
TCC Apply On/Off Off
Batt/Ign Volts Volts 13.5-14.5
Fuel Pump Volts Volts 13.5-14.5
Crank RPM RPM Varies
Air Pump Relay On/Off Off
A/C Request Yes/No No
A/C Clutch On/Off Off
A/C Pressure PSI/Volts Varies
Fan #1 On/Off Off (coolant temperature below 108°C/228°F)
Fan #2 On/Off Off (coolant temperature below 113°C/236°F)
Injector Fault OK/Fault OK
Power Steering Normal/High Normal
Shift Solenoid "A" On/Off Off
Shift Solenoid "B" On/Off Off
P A (PRNDL) Lo/Hi Lo/Hi Park (Lo Lo)
B C (PRNDL) Lo/Hi Lo/Hi Park (Hi Hi)
Trans Range Switch Gear Selected Park or Neutral
TCC PWM Sol. 0-100% 0%
Trans Fluid Temp. -40°C-151°C 75°C-100°C
TCC Brake Switch Released/Applied Released (applied when brake pedal is depressed)
TCC Slip Speed RPM 0-4000 RPM
DTC Ign Counter Varies 0 (Counts Key Cycles)
#DTC Stored Varies 0 (Counts DTC(s) Stored)
SMCC Engaged Yes/No No (Yes when commanded by PCM)
SMCC Inhibited No/Yes No (Yes when commanded by PCM)
Low Oil Light Off/On Off (On when commanded by PCM)
2nd GR. Start SW. On/Off On (Off in 2nd gear)
TCC Off/On Off (On when commanded by PCM)
2nd 3rd Yes/No No/Yes No (Yes, with transmission 2nd gear engaged. No (Yes, with transmission 3rd gear enabled
Time From Start Minutes