AutoCodes – Generic – B1646

B1646 Code - Mirror Passenger Right Circuit Short To Ground

Quick Answer

The Body Control Module (BCM) monitors the Mirror Passenger Motor. Common causes include Faulty Mirror Passenger Motor, Mirror Passenger Motor harness is open or shorted, Mirror Passenger Motor 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: B1646 indicates Mirror Passenger Right Circuit Short To Ground.
Common causes: Common causes include Faulty Mirror Passenger Motor, Mirror Passenger Motor harness is open or shorted, Mirror Passenger Motor 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 10,418

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 24, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B1646 Description

The Body Control Module (BCM) monitors the Mirror Passenger Motor. The BCM sets the OBDII code when the Mirror Passenger Motor is not to factory specifications.

OBDII Code B1646 - Mirror Passenger Right Circuit Short To Ground - AutoCodes.com — B1646 Code - Mirror Passenger Right Circuit Short To Ground

What does this mean?

What are the Possible Causes of the DTC B1646?

Faulty Mirror Passenger Motor
Mirror Passenger Motor harness is open or shorted
Mirror Passenger Motor circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B1646?

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 B1646 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 B1646 code?

Need more information on how to fix the B1646 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1646 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

B1646 Acura — Driver Door LF Antenna Circuit Open
B1646 Honda — Driver Door LF Antenna Circuit Open

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 B1646 Code

1. What are the common symptoms of OBDII code B1646 (Mirror Passenger Right Circuit Short To Ground)?

The common symptoms of code B1646 include malfunctioning or non-operational passenger-side mirror, erratic mirror movement, and in some cases, mirror heating failure.

2. What are the possible causes of OBDII code B1646?

The potential causes of code B1646 include damaged or shorted wiring in the passenger-side mirror circuit, a faulty mirror motor, or a malfunctioning mirror control switch.

3. How can I diagnose OBDII code B1646?

To diagnose code B1646, you can visually inspect the wiring and connections of the passenger-side mirror, test the mirror motor for proper operation, and use a multimeter to check for continuity and shorts in the circuit.

4. What are some repair tips for resolving OBDII code B1646?

Repair tips for addressing code B1646 include repairing or replacing damaged wiring, replacing the mirror motor if faulty, and ensuring proper grounding of the mirror circuit.

5. Can I drive my vehicle with OBDII code B1646 active?

It is generally safe to drive your vehicle with code B1646, but you may experience inconvenience due to the non-operational passenger-side mirror. It is recommended to address the issue promptly to ensure proper functionality.

6. How do I reset OBDII code B1646 after making repairs?

After repairing the underlying issue causing code B1646, you can reset the code using an OBDII scanner or by disconnecting the vehicle's battery for a few minutes to clear the fault memory.

7. Is OBDII code B1646 a serious issue that requires immediate attention?

While code B1646 does not pose a significant safety risk, it is still important to address the problem promptly to restore the proper functioning of the passenger-side mirror and related systems.

8. Can extreme weather conditions cause OBDII code B1646 to trigger?

Extreme weather conditions, such as heavy rain or snow, can potentially contribute to the triggering of code B1646 if water ingress or moisture affects the mirror circuitry. Ensure proper sealing and protection of the mirror components.

9. Are there any preventive measures to avoid OBDII code B1646 in the future?

To prevent code B1646 from occurring, regularly inspect the wiring and components of the mirror circuit for damage, ensure proper maintenance of the mirror system, and avoid exposing the mirror to harsh environmental conditions.

10. Can a DIY enthusiast repair OBDII code B1646, or is professional help recommended?

Depending on your skill level and experience with automotive repairs, you may be able to address code B1646 DIY by following repair guides and utilizing basic tools. However, if you are unsure or uncomfortable, seeking professional assistance is recommended to ensure proper diagnosis and repair.