Test Description

WARNING: This page is about a different car, the 2003 GMC Sonoma, 2003 GMC Jimmy, 2003 Chevrolet S10 Pickup, and 2003 Chevrolet Blazer. However, it is still accessible from the selected car via links, so may be relevant.

The number(s) below refer to the step number(s) on the diagnostic table.

2. The A/C compressor relay output is disabled if engine coolant temperature is above 121°C (250°F).
3. Placing the mode switch in any position other than OFF, along with placing the air temperature control switch in a cold setting, activates A/C operation. For the purpose of this and future steps where A/C operation is necessary, bi-level mode is used for consistent testing.
5. The HVAC control assembly is inoperative when the module does not respond to any operator control requests.
24. Ensure to test both A/C request signal circuits of the A/C high pressure sensor for the listed conditions.

Fig 1: HVAC Compressor Clutch Does Not Engage (4.3L) (1 Of 4)
Courtesy of GENERAL MOTORS CORP.

Fig 2: HVAC Compressor Clutch Does Not Engage (4.3L) (2 Of 4)
Courtesy of GENERAL MOTORS CORP.

Fig 3: HVAC Compressor Clutch Does Not Engage (4.3L) (3 Of 4)
Courtesy of GENERAL MOTORS CORP.

Fig 4: HVAC Compressor Clutch Does Not Engage (4.3L) (4 Of 4)
Courtesy of GENERAL MOTORS CORP.