AutoCodes – Generic – B1686

B1686 Code - Lamp Dome Input Circuit Open

Quick Answer

The Body Control Module (BCM) monitors the Lamp Dome Switch. Common causes include Faulty Lamp Dome Switch, Lamp Dome Switch harness is open or shorted, Lamp Dome Switch 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: B1686 indicates Lamp Dome Input Circuit Open.
Common causes: Common causes include Faulty Lamp Dome Switch, Lamp Dome Switch harness is open or shorted, Lamp Dome Switch 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 5,208

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 Jun 12, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B1686 Description

The Body Control Module (BCM) monitors the Lamp Dome Switch. The BCM sets the OBDII code when the Lamp Dome Switch is not to factory specifications.

OBDII Code B1686 - Lamp Dome Input Circuit Open - AutoCodes.com — B1686 Code - Lamp Dome Input Circuit Open

What does this mean?

What are the Possible Causes of the DTC B1686?

Faulty Lamp Dome Switch
Lamp Dome Switch harness is open or shorted
Lamp Dome Switch circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B1686?

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 B1686 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 B1686 code?

Need more information on how to fix the B1686 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1686 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 B1686 Code

1. What are common symptoms of OBDII code B1686 (Lamp Dome Input Circuit Open)?

- Common symptoms include a malfunctioning dome light, interior lights not turning on, or dashboard warning lights related to the dome light.

2. What can cause OBDII code B1686 to trigger?

- The code B1686 may be triggered due to a faulty dome light switch, damaged wiring in the dome light circuit, or a blown fuse related to the interior lighting.

3. How can I diagnose the cause of OBDII code B1686?

- To diagnose the issue, inspect the dome light switch for proper functioning, check the wiring for any visible damage, and test the fuse related to the dome light circuit.

4. Can a DIY enthusiast repair OBDII code B1686 at home?

- Depending on the root cause, DIY enthusiasts may be able to repair the issue by replacing the dome light switch, repairing damaged wiring, or replacing a blown fuse. However, if unsure, it's best to consult a professional.

5. Is it safe to continue driving with OBDII code B1686 active?

- It is generally safe to drive with OBDII code B1686, but it is important to address the issue promptly to avoid potential safety hazards or further electrical problems.

6. How much does it typically cost to repair OBDII code B1686?

- The cost of repairing OBDII code B1686 can vary depending on the exact cause. Simple fixes like replacing a fuse may be inexpensive, while more complex issues like wiring repairs could be costlier.

7. Can a malfunctioning dome light cause other problems in the vehicle?

- While a malfunctioning dome light itself may not cause major issues, it can be a symptom of underlying electrical problems that may affect other systems in the vehicle.

8. Will disconnecting the battery reset OBDII code B1686?

- Disconnecting the battery may temporarily clear the code, but if the underlying issue is not addressed, the code is likely to reappear once the problem is detected again.

9. How long does it take to repair OBDII code B1686?

- The repair time for OBDII code B1686 can vary depending on the cause and complexity of the issue. Simple fixes may take a short amount of time, while more involved repairs could take longer.

10. Can I use a scan tool to clear OBDII code B1686 without fixing the underlying issue?

- While a scan tool can clear the code temporarily, it is important to address the root cause of OBDII code B1686 to prevent ongoing electrical issues in the vehicle.