GM Service Manual Online
For 1990-2009 cars only
Table 1: HVAC Control Module Scan Tool Data List
Table 2: PCM Scan Tool Data List

HVAC Control Module 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 Switch

Input/Output

On, Off

Off

AC/Heater Door Actual

Door Positions

Counts

Varies

AC/Heater Door Commanded

Door Positions

Counts

Varies

AC/Heater Motor Drive

Door Positions

Stop, Increase, Decrease

Stop

Air Inlet Motor Drive

Door Positions

Fresh Air, Recirc.

Varies

Air Mix Door Left Commanded

Door Positions

Counts

Varies

Air Mix Door Right Commanded

Door Positions

Counts

Varies

Battery Voltage

Input/Output

Volts

13.5-14.5 V

Blower Motor Status

Input/Output

Active, Inactive

Active

Ign. Since Current DTC

Input/Output

Numeric

0

Left Mix Door Actual

Door Positions

Counts

Varies

Left Mix Motor Drive

Door Positions

Stop, Increase, Decrease

Stop

Left Temp. Detent Pos.

Input/Output

0-18

Varies

Mode Select Position

Door Positions

Off, Auto, Defrost, Heater, Htr/Def, Bi-level, Panel

Varies

Pressure Cycle Switch

Input/Output

Low Pressure, Normal

Varies

Recirculate Switch

Input/Output

On, Off

Off

Right Mix Door Actual

Door Positions

Counts

Varies

Right Mix Motor Drive

Door Positions

Stop, Increase, Decrease

Stop

Right Temp Detent Pos.

Input/Output

0-18

Varies

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

629-845 kPa (85-120 psi)

A/C High Side Pressure

Engine Data 2

Volts

Varies

A/C Relay Command

Engine Data 2

On, Off

Varies

A/C Request Signal

Engine Data 2

Yes, No

Varies

ECT Sensor

Engine Data 2

°C/°F

92°C (197°F)

ECT Sensor

Engine Data 2

Volts

1.10-1.45 Volts