B0642
A/C Compressor Circuit
1992-1996 BMW 318is E36 1.8L I4 🇨🇦
Moderate SeverityBody
Description
Malfunction in the A/C compressor electrical control circuit.
Symptoms
- A/C not cooling
- Compressor clutch not engaging
- Compressor clutch always engaged
- A/C system cycling abnormally
Common Causes
- Faulty compressor clutch coil
- Compressor control valve failure (variable displacement)
- Wiring damage
- Ground circuit issue
- Clutch air gap incorrect
Diagnostic Steps
- Test compressor clutch coil resistance
- Check clutch air gap
- Test control valve (if variable)
- Inspect wiring and ground
- Measure voltage at clutch connector
Repair Notes
Replace compressor clutch coil or adjust air gap. For variable compressors, replace control valve.
Related Codes
Other Body Codes
- B0001Driver Frontal Stage 1 Deployment Control
- B0002Driver Frontal Stage 2 Deployment Control
- B0003Passenger Frontal Stage 1 Deployment Control
- B0004Passenger Frontal Stage 2 Deployment Control
- B0005Driver Knee Airbag Deployment Circuit
- B0006Passenger Knee Airbag Deployment Circuit
- B0010Driver Side Airbag Deployment
- B0011Driver Side Airbag Deployment Circuit Open
- B0012Driver Side Airbag Deployment Circuit Short to Ground
- B0013Driver Side Airbag Deployment Circuit Short to Battery
B0642 on Other Vehicles
Common Questions
What does code B0642 mean on a 1992-1996 BMW 318is E36?
B0642 stands for "A/C Compressor Circuit". Malfunction in the A/C compressor electrical control circuit.
What are the symptoms of B0642 on a BMW 318is E36?
Common symptoms of B0642 include: A/C not cooling, Compressor clutch not engaging, Compressor clutch always engaged, A/C system cycling abnormally.
What causes B0642 on a 1992-1996 BMW 318is E36?
Common causes of B0642 include: Faulty compressor clutch coil, Compressor control valve failure (variable displacement), Wiring damage, Ground circuit issue, Clutch air gap incorrect.