GM Service Manual Online
For 1990-2009 cars only

The Transmission Scan Tool Data List contains all Transmission related parameters that are available on the scan tool. The list is arranged in alphabetical order.

Use the Transmission Scan Tool Data List only after performing the following inspections:

    • Powertrain On-Board Diagnostic System Check is completed.
    • No Diagnostic Trouble Codes (DTCs) are present.
    • On-board diagnostics are functioning properly.

Scan tool values from a properly running Transmission may be used for comparison with the Transmission you are diagnosing. The Transmission Scan Tool Data List represents values that would be seen on a normal running engine.

Important: Do not use a scan tool that displays faulty data. Report the scan tool problem to the manufacturer. Use of a faulty scan tool can result in misdiagnosis and unnecessary parts replacement.

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Engine Idling/Upper Radiator Hose Hot/Closed Throttle/Transmission in Park or Neutral/Closed Loop

A/C Relay Command

Transmission Data

On/Off

Off

A/C Request Signal

Transmission Data

Yes/No

No

Diagnostic Mode

Transmission Data

Normal/Check

Normal

Engine Load

Transmission Data

%

19.7% to 49.3%

ECT Sensor

Transmission Data

C°/F°

80-90°C / 176-194°F

Engine Speed

Transmission Data

RPM

650 to 750 RPM

High Electrical Load

Transmission Data

Yes/No

No

IAT Sensor

Transmission Data

C°/F°

Varies with the underhood and ambient temperature

Loop Status

Transmission Data

Open/Closed

Closed Loop

MAF Sensor

Transmission Data

g/s

MIL Command

Transmission Data

Yes/No

No

Overdrive Switch

Transmission Data

On/Off

On/Off

PNP (A/T only)

Transmission Data

P-N/R-D-L

P-N

Shift Request

Transmission Data

1st

1st

Starter Switch

Transmission Data

Released/Cranking

Released

TCC Brake Pedal Switch

Transmission Data

Released/Applied

Released

TCC Enable Solenoid Command

Transmission Data

On/Off

Off

TP Sensor

Transmission Data

%

8-11%

Vehicle Speed Sensor

Transmission Data

km/h/MPH

0 km/h