AutoCodes – Honda – P0685 2009 Honda Accord

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

Quick Answer

The Engine Control Module (ECM) monitors the power inputs. Common causes include Faulty Engine Control Module (ECM) power relay, ECM power relay harness is open or shorted, ECM power relay circuit poor electrical connection. 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 Engine Control Module (ECM) power relay, ECM power relay harness is open or shorted, ECM power relay circuit poor electrical connection.
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 Popularity 9,014

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on May 05, 2019

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0685 2009 Honda Accord Description

The Engine Control Module (ECM) monitors the power inputs. The ECM sets the OBDII code when the ECM remains powered up after the ignition switch has been turned OFF.

OBDII Code P0685 2009 Honda Accord - Engine Control Module Power Relay Control Circuit Open - AutoCodes.com — P0685 2009 Honda Accord Code - Engine Control Module Power Relay Control Circuit Open

What does this mean?

What are the Possible Causes of the DTC P0685 2009 Honda Accord?

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 P0685 2009 Honda Accord?

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 does this mean?

Code Tech Notes

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

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0685 2009 Honda Accord 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 P0685 2009 Honda Accord code?

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

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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.