P0685 2017 Chevrolet Silverado Code - Engine Control Module Power Relay Control Circuit Open
Quick Answer
The P0685 code on a 2017 Chevrolet Silverado indicates a problem with the Engine Control Module (ECM) Power Relay Control Circuit being open. Common causes include Damaged wiring or connectors in the power relay control circuit, Faulty ECM power relay, Blown fuse related to the ECM. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P0685 2017 Chevrolet Silverado indicates Engine Control Module Power Relay Control Circuit Open.
- Common causes
- Common causes include Damaged wiring or connectors in the power relay control circuit, Faulty ECM power relay, Blown fuse related to the ECM.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
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Code P0685 2017 Chevrolet Silverado Description
The P0685 code on a 2017 Chevrolet Silverado indicates a problem with the Engine Control Module (ECM) Power Relay Control Circuit being open. The ECM power relay is responsible for supplying power to the ECM, which is a crucial component that controls various engine functions. When the power relay control circuit is open, it means that there is a break or interruption in the circuit that prevents the ECM from receiving power. This can lead to a range of issues affecting the vehicle's performance, including poor fuel efficiency, rough idling, stalling, and even a no-start condition.
Common Causes of P0685 2017 Chevrolet Silverado
- Damaged wiring or connectors in the power relay control circuit
- Faulty ECM power relay
- Blown fuse related to the ECM
- Malfunctioning ECM
- Corrosion or poor connections in the circuit
Symptoms of P0685 2017 Chevrolet Silverado
- Engine misfires or runs rough
- Poor fuel efficiency
- Engine stalling or hesitation
- Check Engine Light illuminated
- Vehicle may not start
How to Fix P0685 2017 Chevrolet Silverado
- Begin by inspecting the wiring and connectors in the power relay control circuit for any damage or corrosion. Repair or replace as needed.
- Test the ECM power relay to ensure it is functioning correctly. Replace if faulty.
- Check and replace any blown fuses related to the ECM.
- If the issue persists, perform a thorough diagnostic of the ECM to determine if it needs to be replaced.
- Clear the trouble codes, reset the ECM, and test drive the vehicle to ensure the issue has been resolved.
Cost to Fix P0685 2017 Chevrolet Silverado
The typical repair costs for addressing a P0685 code on a 2017 Chevrolet Silverado can range from $150 to $500, depending on the specific cause of the issue and the parts needed for repair. This estimate includes parts and labor. It's important to note that diagnosis time and labor rates at auto repair shops can vary, so it's advisable to check local rates for a more accurate estimate. Keep in mind that rates may be higher at dealerships or in metropolitan areas, while independent shops often charge less.
Tech Notes for P0685 2017 Chevrolet Silverado
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Frequently Asked Questions about P0685 2017 Chevrolet Silverado Code
1. What does OBDII code P0685 mean on a 2017 Chevrolet Silverado?
P0685 indicates an open circuit in the Engine Control Module (ECM) Power Relay Control Circuit, meaning the ECM may not be receiving the proper power supply.
2. What are the common symptoms of code P0685 in a 2017 Chevy Silverado?
Symptoms may include the engine not starting, stalling while driving, no communication with the ECM, or the Check Engine Light being illuminated.
3. What causes the P0685 code to appear on a 2017 Chevrolet Silverado?
Common causes include a faulty ECM power relay, damaged wiring or connectors in the power relay circuit, a blown fuse, or a malfunctioning ECM.
4. How can I diagnose the P0685 code on my Silverado?
Start by inspecting the ECM power relay, checking for blown fuses, and examining the wiring and connectors for damage or corrosion. Use a multimeter to test voltage and continuity in the circuit.
5. Can a faulty ECM power relay cause the P0685 code?
Yes, a malfunctioning ECM power relay is a common cause of this code, as it can prevent proper power delivery to the ECM.
6. Is it safe to drive my 2017 Chevrolet Silverado with the P0685 code?
It is not recommended to drive with this code, as it may cause the engine to stall unexpectedly or fail to start, potentially leaving you stranded.
7. How do I fix the P0685 code on my Silverado?
Repairs may include replacing the ECM power relay, repairing or replacing damaged wiring or connectors in the circuit, replacing blown fuses, or, in rare cases, replacing the ECM.
8. How much does it cost to fix the P0685 code on a 2017 Chevy Silverado?
Repair costs vary depending on the issue. Replacing an ECM power relay typically costs $20–$50 for the part, while wiring repairs or ECM replacement can be significantly more expensive.
9. Can a weak battery trigger the P0685 code?
While unlikely, a weak or failing battery can sometimes cause electrical issues, so it’s worth checking the battery and charging system if the code persists.
10. Do I need to reprogram the ECM after fixing the P0685 code?
In most cases, reprogramming is not required, but if the ECM itself is replaced, it will need to be programmed to match your vehicle's specifications.
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