Diagnostic Aids
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Yukon, 2003 Chevrolet Tahoe, 2003 Chevrolet Suburban, and 2003 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
A/C compressor clutch will not engage under the following conditions:
- The A/C high side line pressure is over 2957 kPa (429 psi).
- The A/C low side line pressure is under 151 kPa(22 psi).
- Throttle angle is at 100 percent.
- Engine speed is more than 5500 RPM.
- Engine coolant temperature (ECT) is more than 121°C (250°F).
- Ambient air temperature is less than 5°C (40°F).