Auto A/C system Air Flow
No air flow
- Inspect blower motor
- Inspect blower motor resistor
- Inspect fuse
- Inspect A/C climate control
- Inspect connectors
- Inspect harness
- Inspect hvac box for
Automotive Cooling system
No cooling
- Inspect A/C switch
- Check refrigerant level
- Inspect clutch relay
- Inspect PCM/BCM/ECM
- Inspect A/C pressure switch
- Inspect compressor clutch coil
- Inspect compressor clutch
- Inspect compressor clutch air gap
- Inspect condenser
- Inspect condenser fan
- Inspect radiator fan
- Inspect evaporator temperature control devices
- Inspect temperature sensors control devices
- Inspect climate control
- Inspect in cabin temperature sensors
- Inspect sun load sensors
- Inspect power steering pressure sensor
Auto a/c system diagnosis by Smell
- Check cabin air filter
- Check evaporator core
- Check hvac box drain tube
- Check re-circulation air door /actuator
- Check hvac box seals
Auto a/c system diagnosis by Noise
Clicking noise
- Check A/C clutch
- Inspect A/C clutch relay
- Inspect cycling switch
- Inspect refrigerant level
- Inspect evaporator temperature sensor
Squealing
- Check drive belt
- Check belt tensioner
- Check compressor for seizing
Grinding
- Check compressor
- Check compressor clutch
Other helpful tips
Replace the receiver driver with every A/C service.
Replace cabin air filter annually
Ensure that service valve caps are in place at every A/C service.