Operation CHARM: Car repair manuals for everyone.

Checking A/C System Operation With No DTCs

Test 1 - 4:




Test 5 - 9:




Test 10 - 12:






SYMPTOM
CHECKING A/C SYSTEM OPERATION WITH NO DTCS

POSSIBLE CAUSES
- Check for PCM DTCs
- Refrigeration system not properly charged
- High press cut-off switch
- Low pressure switch
- Powertrain control module
- A/C clutch coil
- A/C compressor clutch ground circuit open
- (C3) A/C clutch relay output circuit open
- A/C request circuit open
- (A17) fused B+ circuit open
- A/C clutch relay