Error code
OBD2 P0646
OBD2P0646
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.
What it means
A/C Clutch Relay Control Circuit Low.
Severity
moderateCan drive but may experience reduced AC functionality.
Summary
P0646 indicates a low voltage issue in the circuit controlling the AC compressor clutch relay, which is part of the air conditioning system.
Common Causes
- Wiring short to earth
- AC compressor clutch relay failure
Fixes
- Repair or replace the faulty wiring and/or AC compressor clutch relay.
FAQ
What does P0646 mean?
P0646 indicates a low voltage issue in the circuit controlling the AC compressor clutch relay.
Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
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