P0866 - TCM Communication Circuit High
P0866 Possible Causes
- Faulty Transmission Control Module (TCM)
- Transmission Control Module (TCM) harness is open or shorted
- Transmission Control Module (TCM) circuit poor electrical connection
- Faulty Engine Control Module (ECM)
How do I fix code P0866?Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.
Cost of diagnosing the P0866 code
Labor: 1.0The cost of diagnosing the P0866 code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
- Engine Light ON (or Service Engine Soon Warning Light)
P0866 MeaningThe Engine Control Module (ECM) monitors the Transmission Control Module (TCM). The ECM sets the OBDII when there is a problem communicating with the TCM.
P0866 More InformationNeed more information on how to fix the P0866 code?
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Information for specific makes
- P0866 DODGE TCM Communication Circuit High