B0640
A/C Compressor Clutch Relay Circuit
1998-2003 Dodge Durango 4.7L V8
Moderate SeverityBodyGeneric (SAE)
Description
Malfunction in the A/C compressor clutch relay circuit. The relay controls engagement of the A/C compressor.
Symptoms
- A/C not blowing cold air
- Compressor clutch not engaging
- A/C works intermittently
- Relay clicking
Common Causes
- Faulty A/C clutch relay
- Relay control circuit issue
- Low refrigerant triggering cutoff
- BCM or PCM relay driver failure
- Corroded relay socket
Diagnostic Steps
- Check A/C clutch relay
- Test relay with jumper wire
- Check refrigerant pressure
- Test relay control signal from PCM/BCM
- Inspect relay socket for corrosion
Repair Notes
Replace A/C clutch relay. If relay keeps failing, check compressor clutch current draw.
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
B0640 on Other Vehicles
Common Questions
What does code B0640 mean on a 1998-2003 Dodge Durango?
B0640 stands for "A/C Compressor Clutch Relay Circuit". Malfunction in the A/C compressor clutch relay circuit. The relay controls engagement of the A/C compressor.
What are the symptoms of B0640 on a Dodge Durango?
Common symptoms of B0640 include: A/C not blowing cold air, Compressor clutch not engaging, A/C works intermittently, Relay clicking.
What causes B0640 on a 1998-2003 Dodge Durango?
Common causes of B0640 include: Faulty A/C clutch relay, Relay control circuit issue, Low refrigerant triggering cutoff, BCM or PCM relay driver failure, Corroded relay socket.