GM Service Manual Online
For 1990-2009 cars only

Use the Scan Tool Data Display Values and Definitions Information in order to assist in diagnosing the HVAC system. 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 is in PARK.
    • The doors are closed.
    • The windows are closed.
    • The A/C is ON.
    • The ambient air temperatures are at 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 High Side Pressure

Engine Data 2

kPa/psi

1100 kPa/159 psi

A/C High Side Pressure

Engine Data 2

Volts

2.18 Volts

A/C Off For WOT

Engine Data 2

Yes/No

No

A/C Pressure Disable

Engine Data 2

Yes/No

No

A/C Relay Circuit Status

Output Driver Data

OK/Fault/Invalid State

OK

A/C Relay Command

Engine Data 1/Engine Data 2/EGR Data/Misfire Data

On/Off

On

A/C Request Signal

Engine Data 2

Yes/No

Yes