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
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
Spark Advance Degrees Advance 18-24° (varies)
Spark Retard Degrees Timing Retard 0°
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 & 2 ON / OFF ON (coolant temp. above 108° C / 228° F)
OFF (coolant temp. below 104° C / 219° 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)
Hot Engine 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