Engine-Codes.com
Engine-Codes – Honda – P0685 2009 Honda Accord

P0685 2009 Honda Accord Code - Engine Control Module Power Relay Control Circuit Open

Quick Answer

The P0685 code for a 2009 Honda Accord indicates a problem with the Engine Control Module (ECM) Power Relay Control Circuit being open. Common causes include Faulty ECM power relay, Damaged wiring or connectors in the power relay circuit, Blown fuse related to the 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
P0685 2009 Honda Accord indicates Engine Control Module Power Relay Control Circuit Open.
Common causes
Common causes include Faulty ECM power relay, Damaged wiring or connectors in the power relay circuit, Blown fuse related to the 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.
What is this?
Table of contents Created and updated by William Orellana on Sep 11, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0685 2009 Honda Accord Description

The P0685 code for a 2009 Honda Accord 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 such as fuel injection, ignition timing, and emissions systems. When the control circuit is open, it means that there is a break or interruption in the circuit, preventing the relay from functioning properly. This can lead to a loss of power to the ECM, causing a range of performance issues in the vehicle.

OBDII Code P0685 2009 Honda Accord - Engine Control Module Power Relay Control Circuit Open
P0685 2009 Honda Accord Code - Engine Control Module Power Relay Control Circuit Open

Common Causes of P0685 2009 Honda Accord

  1. Faulty ECM power relay
  2. Damaged wiring or connectors in the power relay circuit
  3. Blown fuse related to the ECM power relay
  4. Malfunctioning ECM

Symptoms of P0685 2009 Honda Accord

  1. Engine misfires or runs rough
  2. Decreased fuel efficiency
  3. Engine stalling or difficulty starting
  4. Illuminated check engine light
  5. Limited engine power or acceleration

How to Fix P0685 2009 Honda Accord

  1. Begin by performing a visual inspection of the ECM power relay and its wiring to check for any visible damage or corrosion.
  2. Test the ECM power relay using a multimeter to determine if it is functioning correctly. Replace the relay if necessary.
  3. Check the wiring and connectors in the power relay circuit for any breaks, corrosion, or loose connections. Repair or replace as needed.
  4. Inspect the fuses related to the ECM power relay and replace any blown fuses.
  5. If the issue persists, further diagnostics may be required to determine if the ECM itself is faulty and needs to be replaced.

Cost to Fix P0685 2009 Honda Accord

The cost estimate for repairing a P0685 code on a 2009 Honda Accord can vary depending on the specific cause of the issue. In general, the cost of replacing an ECM power relay can range from $50 to $150, including parts and labor. If additional wiring repairs or an ECM replacement is necessary, the total repair cost could increase to $200 to $500 or more. It is recommended to consult with a qualified mechanic or auto repair shop to obtain a more accurate estimate based on the specific circumstances of the vehicle. Keep in mind that labor rates and part prices can vary, so it's advisable to shop around for the best deal.

What does this mean?

Tech Notes for P0685 2009 Honda Accord

Check all the Engine Control Module (ECM) fuses, if the fuses are OK, then replacing the ECM relay should take care of the problem.

Need more information about the P0685 2009 Honda Accord code?

Need more information on how to fix the P0685 2009 Honda Accord code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0685 2009 Honda Accord code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0685 2009 Honda Accord Code

1. What are the common symptoms of OBDII code P0685 in a 2009 Honda Accord?

- Common symptoms include difficulty starting the vehicle, engine stalling, and the Check Engine Light illuminating on the dashboard.

2. What does the OBDII code P0685 "Engine Control Module Power Relay Control Circuit Open" mean for a 2009 Honda Accord?

- This code indicates that there is an open circuit in the power relay control circuit of the Engine Control Module (ECM).

3. What are the possible causes of OBDII code P0685 in a 2009 Honda Accord?

- Possible causes include a faulty power relay, damaged wiring or connectors in the circuit, a defective ECM, or a blown fuse related to the power relay.

4. How can I diagnose the issue causing OBDII code P0685 in my 2009 Honda Accord?

- A thorough inspection of the power relay, wiring, connectors, and fuses is recommended. Using a multimeter to test for continuity and voltage can help pinpoint the problem.

5. Can I continue driving my 2009 Honda Accord with OBDII code P0685 present?

- It is not recommended to continue driving with this code present, as it can lead to potential issues with starting the engine and overall vehicle performance.

6. Is it possible to repair OBDII code P0685 in a 2009 Honda Accord myself?

- Depending on your automotive repair skills, you may be able to address this issue yourself by checking and replacing the power relay, inspecting wiring, and ensuring proper connections.

7. Will resetting the Check Engine Light make OBDII code P0685 go away in my 2009 Honda Accord?

- Resetting the Check Engine Light may temporarily clear the code, but if the underlying issue causing P0685 is not addressed, the code is likely to reappear.

8. How much does it typically cost to repair OBDII code P0685 in a 2009 Honda Accord at a professional auto repair shop?

- The cost of repairs for this code can vary depending on the specific issue, but it may range from $100 to $300 or more, including parts and labor.

9. Are there any preventive measures I can take to avoid OBDII code P0685 in my 2009 Honda Accord?

- Regularly inspecting and maintaining the electrical components related to the power relay control circuit can help prevent issues that may trigger this code.

10. Can OBDII code P0685 in a 2009 Honda Accord cause any long-term damage if left unresolved?

- Ignoring this code can potentially lead to more severe electrical problems, engine performance issues, and additional complications, so it's advisable to address it promptly.

Discuss the causes and fixes for P0685 2009 Honda Accord OBDII Code

Submit a New Comment

Code P0685 2009 Honda Accord comments

No comments found for this page.