Operation CHARM: Car repair manuals for everyone.

- Preliminary Checks

Most A/C system problems can be detected by a thorough visual and physical inspection of the system and its components.




1. Check the air inlet duct, lower air deflector, condenser to radiator seal, and rear hood seal for missing or damaged parts.

IMPORTANT: The importance of this check cannot be stressed enough because proper heating and cooling depends upon adequate front air flow.

2. Check outer surfaces of radiator and condenser cores, to be sure air flow is not blocked by dirt, leaves, or other foreign material.




3. Check for kinks in hoses and lines. Also check for refrigerant leaks using an electronic leak detector.
4. Check for worn/loose drive belt or malfunctioning belt tensioner.
5. Check blower motor operation at all four speeds.
6. With blower on high, check for equal distribution of air out of all outlets.




7. Check operation of the control mode knob and the distribution of air from the designated outlets.
8. Depress recirc button with blower on high. A noticeable increase in air flow and sound should occur. Indicator should light. The recirc function will not work if in defrost position.
9. Start engine and run until it is up to operating temperature.
10. Check operation of the temperature control knob and the air outlet temperature from hot to cold.




11. Depress A/C button. Indicator should light. Check compressor for clutch engagement, slippage, or noise.
12. Check electric cooling fan operation with A/C On.
13. Turn Off A/C. Compressor clutch should disengage.
14. If any problem is found in any of the previous steps, go to the complaint condition cause charts.