P0686 2018 Chevrolet Silverado Code - Engine Control Module Power Relay Control Circuit Low
Quick Answer
The powertrain relay is a normally open relay. Common causes include Weak battery, Low voltage while cranking, Faulty Engine Control Module (ECM) power relay. 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
- P0686 2018 Chevrolet Silverado indicates Engine Control Module Power Relay Control Circuit Low.
- Common causes
- Common causes include Weak battery, Low voltage while cranking, Faulty Engine Control Module (ECM) power relay.
- 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.
Code P0686 2018 Chevrolet Silverado Description
What are the Possible Causes of the DTC P0686 2018 Chevrolet Silverado?
- Weak battery
- Low voltage while cranking
- Faulty Engine Control Module (ECM) power relay
- ECM power relay harness is open or shorted
- ECM power relay circuit poor electrical connection
- Blown ECM fuse
- Faulty ECM
How to Fix the DTC P0686 2018 Chevrolet Silverado?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0686 2018 Chevrolet Silverado code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P0686 2018 Chevrolet Silverado code?
Need more information on how to fix the P0686 2018 Chevrolet Silverado code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P0686 2018 Chevrolet Silverado code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P0686 2018 Chevrolet Silverado Code
1. What does the P0686 code mean on a 2018 Chevrolet Silverado?
The P0686 code indicates an issue with the Engine Control Module (ECM) Power Relay Control Circuit being too low, which can disrupt the ECM's power supply.
2. What are the common symptoms of code P0686 in a 2018 Chevrolet Silverado?
Common symptoms include difficulty starting the engine, intermittent stalling, poor engine performance, or the vehicle not starting at all.
3. What causes the P0686 code to appear?
Possible causes include a faulty ECM power relay, damaged wiring or connectors in the ECM power relay circuit, a blown fuse, or a malfunctioning ECM.
4. Can a bad battery trigger code P0686 in a Chevrolet Silverado?
Yes, a weak or failing battery can cause voltage issues that might result in the P0686 code being triggered.
5. How do you diagnose the P0686 code on a 2018 Silverado?
Start by checking the ECM power relay, inspecting wiring and connectors for damage, testing the relay circuit for proper voltage, and verifying the integrity of the battery and fuses.
6. Is it safe to drive a 2018 Chevrolet Silverado with a P0686 code?
Driving with a P0686 code is not recommended since it can lead to unpredictable stalling or failure to start, potentially leaving you stranded.
7. How do you fix the P0686 code on a 2018 Chevrolet Silverado?
Repairs may include replacing the ECM power relay, repairing or replacing damaged wiring, cleaning or securing loose connections, or replacing a faulty ECM if needed.
8. How much does it cost to repair the P0686 code on a Silverado?
The repair cost can range from $50 for a simple relay replacement to $1,000 or more if the ECM needs replacement, depending on labor and parts.
9. Can I reset the P0686 code without fixing the issue?
Clearing the code without addressing the root cause will likely result in the code returning, as the underlying issue remains unresolved.
10. Does the P0686 code always mean the ECM is faulty?
No, the ECM itself is not always the issue; often, the problem lies in the relay, wiring, or power circuit connected to the ECM.
Discuss the causes and fixes for P0686 2018 Chevrolet Silverado OBDII Code
Code P0686 2018 Chevrolet Silverado comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
