GM Service Manual Online
For 1990-2009 cars only

Engine Control Module (ECM) or Powertrain Control Module (PCM) Scan Tool Output Controls

Scan Tool Output Control

Additional Menu Selections

Description

A/C Relay

Engine Output Controls

The scan tool displays ON or OFF selections. This command allows you to turn the A/C relay ON or OFF for 5 seconds. When the A/C relay is commanded ON, the A/C compressor clutch should be engaged.