A dedicated power relay (electronic switch) manages the voltage flowing to the PCM, keeping it supplied with enough power to run the powertrain.
If the PCM notices that the voltage signal from the relay indicates that the circuit is open when it shouldn’t be, a P0685 fault code will be stored.
What Does Code P0685 Mean?
The diagnostic hassle code (DTC) P0685 stands for “ECM/PCM electricity Relay manipulate Circuit Open.”
The PCM often examines the voltage condition in the energy relay control circuit that offers battery voltage to the ECM/PCM.
If the laptop sees a low-voltage or no-voltage situation within the circuit, it’ll set the powertrain code P0685.
The ECM/PCM power relay circuits aren’t constantly stressed out an equal manner.
In order for the ECM/PCM to decide that there is a problem with the power relay, there should be a strength to the ECM/PCM from the ignition transfer to awaken parts of the processor first.
Potential Causes of a P0685 Code
The engine computer (PCM) power relay controls the battery voltage to the PCM. If the PCM detects an incorrect voltage signal from the power relay, it will set code P0685.
- Faulty PCM
- Bad PCM power relay
- Problem with the PCM’s electrical wiring
- Broken Fuel Level Sensor
- Fuel Level Sensor joint is exposed or shorted
- Reduced electrical connection to Fuel Level Sensor circuit
- Broken combination meter
What are the Common Symptoms of the P0685 Code?
Our main motive is to achieve customer satisfaction as for us our customers are everything and that’s why we will help you to diagnose the P0685 code by mentioning some major symptoms below:
Common Symptoms
- Check Engine Light On
- Engine Hard Starts and Stalling
- Engine Going in Limp Mode
- Reduced Throttle Response and Acceleration
How to Fix P0685 Code?
Trying to fix a PP0685 code can become frustrating in short order if you don’t have the right equipment and experience to test the engine/powertrain control module power relay. In most cases, it’s best to leave the job to professionals.
Trying to restore a PP0685 code can turn out to be irritating in quick order in case you don’t have the right system and enjoy to test the engine/powertrain control module power relay. In most instances, it’s pleasant to depart the activity to experts.
In case you’re a DIYer who possesses advanced technical knowledge and palms-on revel in, you could test and replace your car’s ECM/PCM strength relay on your very own. it’ll be useful to rely on the perfect restore manual or confer with an internet repair database.
Repair Cost
A “P0685” engine code, which signifies an “ECM/PCM energy Relay control Circuit Open,” normally approach the value to repair will probably range between $100 to $300 relying at the severity of the issue and whether you need to update the relay itself, take a look at wiring connections, or probably even the Powertrain manage Module (PCM) in excessive cases.