PowertrainP0685
SeriousSeverity: Serious - have it checked soon
ECM/PCM Power Relay Control Circuit/Open
Key terms: Control module: a small computer that runs one part of the car · SAE J2012: the standard generic code list · Powertrain: engine, transmission and emissions
1What it means in plain English
The engine computer or one of its output circuits has a fault.
2Common causes
- Engine control module fault
- Power or ground connection problem
- Low battery or charging voltage
- Wiring short or open circuit
- Software or memory fault
3Can I drive?
If the engine runs normally, drive carefully to a workshop for diagnosis. If it runs badly, stalls, or will not restart, have the car towed.
This page gives general information. It is not professional advice. For a definite diagnosis and a repair quote, ask a qualified mechanic to inspect the car.
4Brand data 40
| Brand | Code | Description | System |
|---|---|---|---|
| Ashok Leyland CV | P0685 | Engine Coolant Pump. Component Stuck Brand | Powertrain |
| BAIC Motor | P0685 | Main relay fault Brand | Powertrain |
| Mercedes-Benz | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| BYD | P0685 | Main relay fault Brand | Powertrain |
| Chery | P0685 | Main Relay Malfunction Brand | Powertrain |
| Chrysler | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| Daewoo | P0685 | Main Relay Malfunction Brand | Powertrain |
| Daihatsu | P0685 | IGCT relay error Brand | Powertrain |
| DFFS | P0685 | Main relay fault Brand | Powertrain |
| DFFX | P0685 | Main relay failure Brand | Powertrain |
| DFXK | P0685 | Main relay faulty Brand | Powertrain |
| EOBD | P0685 | ECM/PCM-virtareleen ohjauspiiri/auki Brand | Powertrain |
| Ford | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| Geely | P0685 | Main Relay Output Fault Brand | Powertrain |
| GM | P0685 | ECM/PCM Power Relay Control Circuit/Open Brand | Powertrain |
| Great Wall | P0685 | Main relay fault Brand | Powertrain |
| Hafei | P0685 | ECM/PCM Power Relay Control Circuit/Open Brand | Powertrain |
| Holden | P0685 | Engine Controls Ignition Relay Control Circuit Brand | Powertrain |
| Honda | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| Hyundai | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| Isuzu | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| Land Rover | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| Mahindra | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| Maserati | P0685 | Automatic Shut Down/Main Control Circuit Brand | Powertrain |
| Mazda | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| Mitsubishi | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| Opel | P0685 | ECM/PCM Power Relay Control Circuit/Open Brand | Powertrain |
| Perodua | P0685 | IGCT relay error Brand | Powertrain |
| Peugeot | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| Porsche | P0685 | Start delay due to undervoltage Brand | Powertrain |
| Proton | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| Saab | P0685 | ECM/PCM Power Relay Control Circuit/Open Brand | Powertrain |
| MG (SAIC) | P0685 | ECM/PCM Power Relay Control Circuit/Open Brand | Powertrain |
| Subaru | P0685 | ECM/PCM Power Relay Control Circuit/Open SAE | Powertrain |
| Suzuki | P0685 | ECM / PCM Power Relay Control Circuit / Open Brand | Powertrain |
| SWM Motor | P0685 | Main relay fault Brand | Powertrain |
| Tata | P0685 | Command For Main Relay Brand | Powertrain |
| Toyota | P0685 | Main relay fault Brand | Powertrain |
| Volvo | P0685 | Main Relay (power hold) Brand | Powertrain |
| Volkswagen | P0685 | ECM Power Relay Control Circuit (J271): Open Circuit Brand | Powertrain |
Legend: SAE is the generic J2012 description; Brand is text taken from that manufacturer’s data. Manufacturer rows keep the wording and language of the source data, and non-English text is tagged so screen readers pronounce it correctly.
5Extended variant codes 5
These 7-character codes are manufacturer-specific variants of P0685 and may be reported by some scan tools.
| Brand | Code | Description | System |
|---|---|---|---|
| Mercedes-Benz | P068500 | The output for relay 'Circuit 87' has an electrical fault or an open circuit. Brand | Powertrain |
| Hyundai | P068500 | No description available | Powertrain |
| SsangYong | P068500 | ECU power relay control circuit Brand | Powertrain |
| Mercedes-Benz | P068501 | Der Ausgang für Relais 'Klemme 87 (Verbrennungsmotor)' hat einen elektrischen Fehler oder Unterbrechung.Es liegt ein allgemeiner elektrischer Fehler vor. Brand | Powertrain |
| Mercedes-Benz | P068549 | Der Ausgang für Relais 'Klemme 87 (Verbrennungsmotor)' hat einen elektrischen Fehler oder Unterbrechung. Es liegt ein interner elektrischer Fehler vor. Brand | Powertrain |
6Related codes
Browse Pxxx codes or P068xx codes.