What is P0645 fault code and what does it mean? What is the description for Air Conditioning (A/C Clutch Relay Circuit Malfunction)? How do you fix the P0645 fault code What are the causes and symptoms of the P0645 error code?
What is the P0645 fault code? What does it signify?
The compressor clutch controls the pressure of the A/C system. A relay is located on the compressor clutch. This relay activates or disables the compressor via either the powertrain control module or engine control module. This circuit may be complex depending on vehicle model and application. There may be multiple control modules connected to it. The fault code P0645 will trigger the PCM/ECM and other control modules to detect faults in the compressor clutch relay circuit control circuit. This will cause the check engine light to turn on. Some vehicle models may require the fault to be repeated for 8 or more times before the check engine light will illuminate.
P0645 fault codes can be found on many vehicles, including Dodge, Jeep, Chrysler and Opel models.
What are the possible causes of the P0645 Fault code?
Below are some reasons to set fault code P0645:
- – A/C compressor clutch relay defective
- – Defective A/C compressor clutch
- – Defective air conditioner compressor
- – The relay’s wiring and/or connectors have been damaged, burnt, disconnected, corroded or shorted.
- – Ground wire causing weak electrical signal
- – An issue with the wiring of the bus harness for the CAN (Control Area Network).
- – Blown Fuses
- – Defective PCM/ECM or other control modules
What are the symptoms of P0645 Fault code?
These symptoms may be present in vehicles with code P0645.
- – Illumination at the check engine lights
- – A/C fault light on
- – Air conditioner not working properly or at all
How to Fix the P0645 Fault Code
There are several repairs that can resolve the P0645 fault code.
- – Repair of damaged wires, connectors and open or short circuit issues associated with the A/C clutch control circuit
- – Replacing your A/C clutch relay
- – Replacing blown fuse
- – Cleaning corrosion on connectors
- – Fixing poor electricity connections
- – Replacing the A/C compressor clutch
- Repairing an air conditioner compressor that is not working properly
- Troubleshooting the PCM/ECM or other control module
All cables should be thoroughly inspected. Repair or replace any cables that have corroded or burnt. Because of the complexity of the system, certain models may have many relays or fuses. You should inspect them all.
Conduct continuity testing to ensure the integrity of cables and associated modules. Verify all ground wires. Unless specified otherwise, the normal resistance of connections should not exceed 0 ohms. If there is no continuity, it could be caused by a problem in the system. Repair it or replace it. If that fails, you can inspect the A/C clutch relay to determine if it needs replacing.
How serious is the P0645 fault code?
This code’s severity depends on how attentive you are to your air conditioner. Some drivers prefer to open their windows and not use the air conditioning. Others need air conditioning. This code won’t cause safety problems that could endanger you and your passengers.
