AutoCodes – Ford – P0686 Ford

P0686 Ford Code - Engine Control Module Power Relay Control Circuit Low

Quick Answer

The Engine Control Module (ECM) monitors the power inputs. 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 Ford 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.

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Code Popularity 5,441

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
Cost to Diagnose
FAQs
Comments
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Code P0686 Ford Description

The Engine Control Module (ECM) monitors the power inputs. The ECM sets the OBDII code when the ECM detects a low power voltage input.

OBDII Code P0686 Ford - Engine Control Module Power Relay Control Circuit Low - AutoCodes.com — P0686 Ford Code - Engine Control Module Power Relay Control Circuit Low

What does this mean?

What are the Possible Causes of the DTC P0686 Ford?

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
Faulty ECM

How to Fix the DTC P0686 Ford?

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 Ford 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 Ford code?

Need more information on how to fix the P0686 Ford code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0686 Ford 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 P0686 Ford Code

1. What are common symptoms of OBDII code P0686 in a Ford vehicle?

- Common symptoms include difficulty starting the engine, engine stalling, and the Check Engine light being illuminated on the dashboard.

2. What can cause the OBDII code P0686 to trigger in a Ford vehicle?

- The code P0686 is typically triggered by a malfunction in the engine control module power relay control circuit, often caused by a faulty relay or damaged wiring.

3. How can I diagnose the cause of OBDII code P0686 in my Ford vehicle?

- To diagnose the issue, you can use a diagnostic scanner to retrieve the trouble codes, inspect the engine control module power relay and related wiring for any visible damage, and perform circuit testing using a multimeter.

4. Can I drive my Ford vehicle with the OBDII code P0686 present?

- It is not recommended to drive the vehicle with the code P0686 present, as it can lead to potential engine performance issues and may cause further damage if left unaddressed.

5. How can I repair the Engine Control Module Power Relay Control Circuit Low issue in my Ford vehicle?

- Repairing the P0686 code involves inspecting and, if necessary, replacing the engine control module power relay, repairing any damaged wiring, and clearing the trouble codes using a diagnostic scanner.

6. Is it possible to reset the OBDII code P0686 in a Ford vehicle without fixing the underlying issue?

- While you can clear the trouble code using a diagnostic scanner, it is important to address the root cause of the problem to prevent the code from reoccurring.

7. Can a DIY enthusiast fix the OBDII code P0686 in a Ford vehicle?

- Depending on your skill level and access to tools, a DIY enthusiast may be able to address the P0686 code by replacing the engine control module power relay and checking the related wiring for any damage.

8. Are there any preventive maintenance steps to avoid OBDII code P0686 in a Ford vehicle?

- Regularly inspecting the engine control module power relay and related wiring for signs of wear or damage can help prevent the occurrence of the P0686 trouble code.

9. How long does it take to repair the OBDII code P0686 in a Ford vehicle?

- The repair time for the P0686 code can vary depending on the extent of the issue and your experience level. It may take anywhere from 30 minutes to a few hours to complete the repair.

10. Will fixing the OBDII code P0686 improve my Ford vehicle's performance?

- Addressing the P0686 code and restoring proper function to the engine control module power relay control circuit can help improve engine performance and overall vehicle operation.