A/C Request A Circuit High
The A/C request input A reads stuck high — typically a short to battery voltage. The ECM cannot pull the line low to read switch state, so the A/C compressor request is treated as invalid and the clutch stays disengaged.
Affected components
- Ac request input a
Common causes
- High likelihood: Request wire shorted to battery voltage
- Low likelihood: Connector pins corroded - high contact resistance
- Low likelihood: Supply wire pinched against B+ source
Diagnostic notes
- The malfunction indicator lamp may illuminate
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.