AutoCodes – Volkswagen – P0686 Volkswagen

P0686 Volkswagen 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 Volkswagen 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 15,412

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

What does this mean?

What are the Possible Causes of the DTC P0686 Volkswagen?

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 Volkswagen?

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 Volkswagen 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.

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

Need Help with the Code?

Get the P0686 Volkswagen 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 Volkswagen Code

1. What are the common symptoms of OBDII code P0686 in a Volkswagen?

- Common symptoms include engine stalling, difficulty starting the vehicle, and the illumination of the check engine light.

2. What does the OBDII code P0686 indicating "Engine Control Module Power Relay Control Circuit Low" mean for a Volkswagen?

- This code suggests that the Engine Control Module (ECM) is detecting a low voltage condition in the power relay control circuit.

3. What are the possible causes of OBDII code P0686 in a Volkswagen?

- The code P0686 in a Volkswagen may be caused by a faulty power relay, damaged wiring or connectors in the control circuit, or a malfunctioning ECM.

4. How can I diagnose the cause of OBDII code P0686 in my Volkswagen?

- To diagnose the issue, you can perform a visual inspection of the wiring and connectors, test the power relay, and use a multimeter to check for voltage irregularities in the control circuit.

5. Is it safe to continue driving my Volkswagen with OBDII code P0686?

- It is not recommended to drive your vehicle with a persistent P0686 code, as it can lead to potential engine performance issues and further damage if left unresolved.

6. Can I reset the OBDII code P0686 in my Volkswagen with a diagnostic scanner?

- Yes, you can reset the code using a diagnostic scanner, but it is crucial to address the underlying issue causing the code to prevent it from reoccurring.

7. What are some repair tips for fixing OBDII code P0686 in a Volkswagen?

- Repair tips may include replacing the power relay, repairing or replacing damaged wiring, ensuring proper connections, and, if needed, replacing the ECM.

8. How much does it typically cost to repair OBDII code P0686 in a Volkswagen?

- The cost of repairing OBDII code P0686 in a Volkswagen can vary depending on the specific issue, but it may range from $100 to $500 or more, including parts and labor.

9. Can a DIY enthusiast fix OBDII code P0686 in a Volkswagen?

- While some experienced DIYers may be able to address the issue, diagnosing and repairing OBDII code P0686 often requires advanced automotive knowledge and tools, so it is recommended to seek professional help.

10. How can I prevent OBDII code P0686 from occurring in my Volkswagen?

- Regular maintenance, timely inspection of electrical components, and addressing any issues promptly can help prevent the occurrence of OBDII code P0686 in your Volkswagen.