Error code
OBD2 P0666
OBD2P0666
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.
What it means
PCM/ECM/TCM Internal Temperature Sensor Circuit.
Severity
moderateCan drive, but monitor symptoms and address soon.
Summary
P0666 indicates an issue with the internal temperature sensor circuit in the Powertrain Control Module (PCM), Engine Control Module (ECM), or Transmission Control Module (TCM).
Common Causes
- Poor wiring connection
- Faulty internal temperature sensor
- Issues within the ECM
Fixes
- Replace faulty internal temperature sensor or repair wiring issues.
FAQ
What does P0666 mean?
P0666 indicates a malfunction in the internal temperature sensor circuit of the PCM, ECM, or TCM.
How do I fix P0666?
Fixing P0666 typically involves replacing the faulty internal temperature sensor or repairing any wiring issues.
Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
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