AutoCodes – Generic – B0985

B0985 Code - Right Headlamp Light Distribution Shutter Control Circuit Malfunction

Quick Answer

Battery positive voltage is applied to the headlamp control module at all times. Common causes include Faulty Right Headlamp Assembly, Right Headlamp Assembly harness is open or shorted, Right Headlamp Assembly 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: B0985 indicates Right Headlamp Light Distribution Shutter Control Circuit Malfunction.
Common causes: Common causes include Faulty Right Headlamp Assembly, Right Headlamp Assembly harness is open or shorted, Right Headlamp Assembly 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 5,261

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 Mar 11, 2021

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B0985 Description

Battery positive voltage is applied to the headlamp control module at all times. The headlamp control module has a normal operational voltage range of about 12.5-16 V and is only fully functional with the ignition switch is in the RUN position and the headlamp switch in the AUTO position. The communications enable signal from the Body Control Module (BCM) wakes the headlamp control module microprocessor. The headlamp control module receives serial data messages from the Engine Control Module (ECM), Transmission Control Module (TCM), Electronic Brake Control Module (EBCM), and BCM with information regarding power mode, speed, steering angle, transmission gear selection, and headlamp switch status. The headlamp control module calculates the headlamp angle and sends commands to the left and right adaptive forward lighting system headlamp actuators. The headlamp actuators drive the headlamps to the position commanded by the headlamp control module. The headlamp control module monitors the headlamp actuator motor control circuits for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a DTC will be stored in memory and the driver will be notified with a message displayed over the driver information center located on the instrument cluster.

OBDII Code B0985 - Right Headlamp Light Distribution Shutter Control Circuit Malfunction - AutoCodes.com — B0985 Code - Right Headlamp Light Distribution Shutter Control Circuit Malfunction

What does this mean?

What are the Possible Causes of the DTC B0985?

Faulty Right Headlamp Assembly
Right Headlamp Assembly harness is open or shorted
Right Headlamp Assembly circuit poor electrical connection

How to Fix the DTC B0985?

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 B0985 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 B0985 code?

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Need Help with the Code?

Get the B0985 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

B0985 Buick — Right Headlamp Light Distribution Shutter Control Circuit Malfunction
B0985 Cadillac — Right Headlamp Light Distribution Shutter Control Circuit Malfunction
B0985 Chevrolet — Right Headlamp Light Distribution Shutter Control Circuit Malfunction
B0985 GMC — Right Headlamp Light Distribution Shutter Control Circuit Malfunction

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 B0985 Code

1. What are the common symptoms of OBDII code B0985 (Right Headlamp Light Distribution Shutter Control Circuit Malfunction)?

The common symptoms include the right headlamp not working properly, erratic headlight behavior, or the headlight not adjusting properly while driving.

2. What could cause OBDII code B0985 to trigger?

Possible causes of this code include a faulty light distribution shutter control module, damaged wiring or connectors in the headlamp circuit, or a malfunctioning headlight control switch.

3. How can I diagnose the source of the Right Headlamp Light Distribution Shutter Control Circuit Malfunction?

To diagnose the issue, you may need to perform a visual inspection of the headlamp assembly, check the wiring and connectors for any signs of damage, and use a multimeter to test the circuit for proper voltage and continuity.

4. Can I still drive my vehicle with the B0985 trouble code?

It is not recommended to drive your vehicle with the B0985 code present, as it can affect the proper functioning of your right headlamp, leading to reduced visibility and potentially unsafe driving conditions.

5. How can I repair OBDII code B0985 on my own?

Repairing this code may involve replacing the light distribution shutter control module, repairing or replacing damaged wiring or connectors, or resetting the headlight control system using a diagnostic tool.

6. Will resetting the trouble codes make the B0985 code disappear permanently?

Resetting the trouble codes may temporarily clear the B0985 code, but if the underlying issue causing the malfunction is not resolved, the code is likely to reappear after driving a certain distance or under specific conditions.

7. Is it safe to continue driving if only the light distribution shutter is malfunctioning?

Driving with a malfunctioning light distribution shutter can affect the proper functioning of your headlamp, leading to uneven light distribution and reduced visibility, especially at night or in low-light conditions.

8. Can extreme weather conditions cause the Right Headlamp Light Distribution Shutter Control Circuit Malfunction?

Extreme weather conditions like heavy rain, snow, or extreme temperatures can potentially damage the headlamp circuitry or components, leading to the triggering of the B0985 trouble code.

9. How much does it typically cost to repair OBDII code B0985 at a professional auto repair shop?

The cost of repairing the Right Headlamp Light Distribution Shutter Control Circuit Malfunction can vary depending on the specific cause of the issue, but it may range from $100 to $300 for parts and labor.

10. Is it necessary to have the B0985 trouble code repaired immediately?

It is recommended to address the Right Headlamp Light Distribution Shutter Control Circuit Malfunction promptly to ensure proper headlight functionality and maintain safe driving conditions, especially during nighttime or adverse weather.