P0685 code meaning, causes and symptoms
P0685 means ecm / pcm power relay control circuit / open.
P0685 code meaning is one of the most common OBD-II searches when a warning light appears on the dashboard.
Drivers searching for P0685 usually want to know what the code means, whether the car is safe to drive and what part may need testing first.
Because P0685 can appear on multiple makes and models, it is important to combine the code meaning with live data, symptoms and any other stored faults.
A proper diagnosis for P0685 should normally include a scan tool check, freeze-frame review and inspection of the components related to ecm / pcm power relay control circuit / open.
Severity: Medium
Driving advice: Whether you can keep driving depends on how the vehicle is behaving. If there is rough running, loss of power, overheating or stalling, diagnose it as soon as possible.
FAQs
What does P0685 mean?
P0685 means ecm / pcm power relay control circuit / open.
What can cause P0685?
Causes can include failed components, wiring faults, leaks, pressure issues, bad readings or another upstream fault affecting the same system.
Is P0685 serious?
Severity depends on how the vehicle is behaving and what system is affected. Some codes are minor, while others can affect engine performance, emissions or drivability.