P0863 OBD-II: TCM Communication Circuit

P0863 Severity

Urgent

Should you fix P0863 yourself?

Identifying an OBD code is just the start of a complete diagnostic routine. Most trouble codes are caused by a sensor reporting a value that is out of range. Just replacing a sensor may not fix underlying issues. Be sure to understand the code, the part or system in your car that the code refers to, and the risks of delaying professional repair.

Proper diagnosis will save you time and money on unnecessary repairs.

Urgent codes indicate immediate action is necessary. These are urgent and significant malfunctions that can cause severe damage to the vehicle or harm the driver and passengers.

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What causes OBD-II fault code P0863?

If the Transmission Control Module (TCM) cannot communicate with other modules or the engine control module (PCM) can not communicate with the PCM, code P0863 will be set.

OBD II Fault Code

OBD II P0863

OBD-II Code Transmission may not shift properly is defined as a TCM Communication Circuit

If the Transmission Control Module (TCM) cannot communicate with other modules or the engine control module (PCM) can not communicate with the PCM, code P0863 will be set.

Transmission may not shift properly Symptoms

Increased fuel consumption
Transmission may not shift properly

Common Problems That Trigger the P0863 Code

Transmission Control Module (TCM) failure
Wiring issue

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OBD II Fault Code

OBD II P0863

OBD-II Code Transmission may not shift properly is defined as a TCM Communication Circuit

If the Transmission Control Module (TCM) cannot communicate with other modules or the engine control module (PCM) can not communicate with the PCM, code P0863 will be set.

Transmission may not shift properly Symptoms

Increased fuel consumption
Transmission may not shift properly

Common Problems That Trigger the P0863 Code

Transmission Control Module (TCM) failure
Wiring issue

P0863 OBD-II: TCM Communication Circuit

Should you fix P0863 yourself?

What causes OBD-II fault code P0863?

Need a P0863 diagnosis? Trust our experts.

OBD II Fault Code

Transmission may not shift properly Symptoms

Common Problems That Trigger the P0863 Code

OBD Code Resources

Ask our experts about P0863.

Other OBD-II Codes

OBD II Fault Code

Transmission may not shift properly Symptoms

Common Problems That Trigger the P0863 Code