GM Service Manual Online
For 1990-2009 cars only
Table 1: PCM Scan Tool Data List
Table 2: Roof and Door Module (RDM) Scan Tool Data List

Use the Scan Tool Data Display Values and Definitions Information in order to assist in diagnosing the powertrain control module (PCM) problems. Compare the vehicles actual scan tool data with the typical data display value table information. Use the data information in order to aid in understanding the nature of the problem when the vehicle does not match with the typical data display values.

The scan tool data values were taken from a known good vehicle under the following conditions:

    • The ignition switch is in the ON position.
    • The engine is running at idle.
    • The vehicle transmission is in the PARK position.
    • The doors are closed.
    • The windows are closed.
    • The A/C is ON.
    • The ambient air temperature is between 22-27°C (70-80°F).

PCM Scan Tool Data List

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Engine idling, A/C ON, ambient air temperature between 22-27°C (70-80°F)

A/C Pressure Sensor

Engine Data 2

psi/kPa

Varies

A/C Pressure Sensor

Engine Data 2

Volts

Varies

A/C Relay Command

Engine Data 1

Engine Data 2

On/Off

On

A/C Request Signal

Engine Data 2

Yes/No

Yes

Roof and Door Module (RDM) Scan Tool Data List

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Engine idling, A/C ON, ambient air temperature between 22-27°C (70-80°F)

A/C Request

RDM

Yes/No

Yes