Technical Definition:
Engine Control Module (ECM) / Powertrain Control Module (PCM) Power Relay Control Circuit Low
Trouble Code: P0686
Address: 0x0686
System: Powertrain
Subsystem: Computer and Auxiliary Output Circuits
Address: 0x0686
System: Powertrain
Subsystem: Computer and Auxiliary Output Circuits
Technical Description:
Possible Causes:
Possible Symptoms:
Engine Control Module Voltage Error Low
Possible Solutions:
OBD-II Trouble Code Type:
Diagnostic Step:
Tech Notes:
– Weak battery- Low voltage while cranking
– Faulty Engine Control Module (ECM) relay
– Blown ECM fuse
– Faulty ECM
– ECM harness is open or shorted
– ECM circuit poor electrical connection