Error code

OBD2 P0686

OBD2P0686
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.

What it means

ECM/PCM Power Relay Control Circuit Low.

Severity

moderateCan drive, but may experience reduced performance or stalling.

Summary

P0686 indicates a low voltage issue in the ECM/PCM power relay control circuit, which is part of the engine's electronic control system.

Common Causes

  • Wiring short to earth
  • ECM/PCM power relay failure
  • ECM malfunction

Fixes

FAQ

What does P0686 mean?

P0686 indicates a low voltage issue in the ECM/PCM power relay control circuit.

How serious is P0686?

Moderately serious. It can affect engine performance and may cause stalling, but driving is possible with caution.

Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.