GM Service Manual Online
For 1990-2009 cars only
Table 1: HVAC Control Module Scan Tool Output Controls
Table 2: PCM Scan Tool Output Controls
Table 3: Rear HVAC/RSA Module

HVAC Control Module Scan Tool Output Controls

Scan Tool Output Control

Additional Menu Selection(s)

Description

A/C Request

Miscellaneous Tests

When you select ON, the HVAC control module changes the state of the A/C Request parameter to ON and transmits a clutch enable message to the powertrain control module (PCM) over the class 2 serial data circuit.

Air Inlet Door

Motor/Actuator Tests

When you select ON, the HVAC control module commands the recirculation actuator toward the maximum door position. The actuator moves the door to the recirculation position. When you select OFF, the HVAC control module commands the recirculation actuator toward the minimum door position. The actuator moves the door to the outside air position.

Blower Motor

Motor/Actuator Tests

When you select ON, the HVAC control module commands the blower motor to maximum speed. The blower motor operates at maximum speed until you select OFF. The HVAC control module must be in the ON state before selecting the output control.

HVAC Actuator Recalibration

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When you select RESET, the HVAC control module recalibrates the maximum and minimum door positions of each HVAC door. The ambient air temperature display is set to the current value of the Outside Air Temp. Raw parameter.

Inside Air Temperature Fan

Motor/Actuator Tests

When you select OFF, the HVAC control module commands the inside air temperature fan OFF. The fan remains OFF until you select ON. The normal state of the inside air temperature fan is ON.

Left Mix Motor

Motor/Actuator Tests

When you select ON, the HVAC control module commands the left air temperature actuator toward the maximum door position. The actuator moves the door to the full hot position. When you select OFF, the HVAC control module commands the left air temperature actuator toward the minimum door position. The actuator moves the door to the full cold position.

Mode Door Position

Motor/Actuator Tests

When you select ON, the HVAC control module commands the mode actuator toward the maximum door position. The actuator moves the door to the panel position. When you select OFF, the HVAC control module commands the mode actuator toward the minimum door position. The actuator moves the door to the floor position.

Right Mix Motor

Motor/Actuator Tests

When you select ON, the HVAC control module commands the right air temperature actuator toward the maximum door position. The actuator moves the door to the full cold position. When you select OFF, the HVAC control module commands the right air temperature actuator toward the minimum door position. The actuator moves the door to the full hot position.

PCM Scan Tool Output Controls

Scan Tool Output Control

Additional Menu Selection(s)

Description

A/C Relay

Engine Output Controls

The engine must be running and the PCM must receive an A/C request from the HVAC control module in order to enable the output control. The PCM de-energizes the A/C compressor clutch relay when you select OFF. The relay remains de-energized until you select ON.

Rear HVAC/RSA Module

Scan Tool Output Control

Additional Menu Selections

Description

Displays(s) Test

Special Functions

The Rear HVAC/RSA module will illuminate all indicators and display segments on the module display.