GM Service Manual Online
For 1990-2009 cars only
Table 1: Heating And Air Conditioning Scan Tool Output Controls
Table 2: PCM Scan Tool Output Controls

The special functions menu allows you to test the A/C components by operating them independently of the IPM. When using the special functions, follow the on screen prompts to test the A/C system components.

Heating And Air Conditioning Scan Tool Output Controls

Scan Tool Output Control

Additional Menu Selection(s)

Description

A/C Signal Request Test

Special Functions

The scan tool displays Active or Inactive selections. This function allows you to activate the A/C request signal from the heater and A/C control. When Active is selected, the A/C OFF LED on the heater and A/C control should be OFF.

Air Circulation Valve Test

Special Functions

The scan tool displays Active or Inactive selections. This function allows you to test the air circulation valve operation by driving it to its active or inactive stops The air circulation LED will illuminate on the heater and A/C control when air recirculation is active.

Blower Motor Test

Special Functions

The scan tool displays Up and Down selections. This function allows you to actuate the blower motor at each speed setting.

Compressor Test

Special Functions

This function activates the A/C compressor and runs the A/C at the lowest temperature setting to test the A/C compressor operation.

Defrost Air Mix Door Motor Test

Special Functions

The scan tool displays Increase and Decrease selections. This function allows you to test the defrost air mix door motor operation by driving it to its minimum and maximum stops.

Display Test

Special Functions

The scan tool displays Off or On selections. When you select On, all segments of the HVAC control panel should illuminate. When you select Off, all segments of the HVAC control panel be blank.

Floor Air Mix Door Motor Test

Special Functions

The scan tool displays Increase and Decrease selections. This function allows you to test the floor air mix door motor operation by driving it to its minimum and maximum stops.

Heating Cutoff Valve Test

Special Functions

The scan tool displays Active or Inactive selections. This function allows you to test the heating cutoff valve operation by manually turning it ON and OFF.

Interior Air Mix Door Motor Test

Special Functions

The scan tool displays Increase and Decrease selections. This function allows you to test the interior air mix door motor operation by driving it to its minimum and maximum stops.

Left Air Mix Door Motor Test

Special Functions

The scan tool displays Increase and Decrease selections. This function allows you to test the left air mix door motor operation by driving it to its minimum and maximum stops.

Right Air Mix Door Motor Test

Special Functions

The scan tool displays Increase and Decrease selections. This function allows you to test the right air mix door motor operation by driving it to its minimum and maximum stops.

PCM Scan Tool Output Controls

Scan Tool Output Control

Additional Menu Selection(s)

Description

A/C Relay

Engine Output Controls

The scan tool displays On or Off selections. This command allows you to command the A/C compressor relay ON or OFF. When the A/C compressor relay is commanded ON, the A/C compressor clutch should be engaged.