P2678 OBD-II: Coolant Degassing Valve Control Circuit/Open

P2678 Severity

Urgent

Should you fix P2678 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.

Schedule Diagnosis

What causes OBD-II fault code P2678?

The Coolant Degassing Valve allows Coolant that has been vaporized to return to the pressurized overflow tank. If this Valve does not operate as requested by the engine computer (PCM), code P2678 will be stored.

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