AutoCodes – Generic – U1729

U1729 Code - Right High Beam Control Module Lost Communication With Right Headlamp Horizontal Motor

Quick Answer

The Local Interconnect Network (LIN) Bus consists of a single wire with a transmission rate of 10.417 Kbit/s. Common causes include Faulty Right Headlamp Horizontal Motor, Right Headlamp Horizontal Motor harness is open or shorted, Right Headlamp Horizontal 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: U1729 indicates Right High Beam Control Module Lost Communication With Right Headlamp Horizontal Motor.
Common causes: Common causes include Faulty Right Headlamp Horizontal Motor, Right Headlamp Horizontal Motor harness is open or shorted, Right Headlamp Horizontal 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 802

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 07, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U1729 Description

The Local Interconnect Network (LIN) Bus consists of a single wire with a transmission rate of 10.417 Kbit/s. The serial data is transmitted over a LIN circuit between a master control module and other LIN devices within a particular subsystem. If serial data communication is lost between any of the LIN devices on the LIN bus network, the master control module will set a no communication code against the non-communicating LIN device. The Diagnostic Trouble Code (DTC) will set when a supervised periodic message to the Right High Beam Control Module from the Right Headlamp Horizontal Motor has not been received.

OBDII Code U1729 - Right High Beam Control Module Lost Communication With Right Headlamp Horizontal Motor - AutoCodes.com — U1729 Code - Right High Beam Control Module Lost Communication With Right Headlamp Horizontal Motor

What does this mean?

What are the Possible Causes of the DTC U1729?

Faulty Right Headlamp Horizontal Motor
Right Headlamp Horizontal Motor harness is open or shorted
Right Headlamp Horizontal Motor circuit poor electrical connection
Faulty Right High Beam Control Module

How to Fix the DTC U1729?

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 U1729 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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Information for Specific Makes

U1729 Buick — Right High Beam Control Module Lost Communication With Right Headlamp Horizontal Motor
U1729 Cadillac — Right High Beam Control Module Lost Communication With Right Headlamp Horizontal Motor
U1729 Chevrolet — Right High Beam Control Module Lost Communication With Right Headlamp Horizontal Motor
U1729 GMC — Right High Beam Control Module Lost Communication With Right Headlamp Horizontal Motor

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 U1729 Code

1. What are the common symptoms of OBDII code U1729?

The common symptoms of code U1729 include the right high beam not functioning properly, issues with the right headlamp horizontal motor, and a dashboard warning light indicating a communication problem.

2. What can cause OBDII code U1729 to trigger?

Code U1729 is typically triggered when there is a communication breakdown between the right high beam control module and the right headlamp horizontal motor. This can be caused by wiring issues, a faulty control module, or a malfunctioning motor.

3. How can I diagnose the reason behind OBDII code U1729?

Diagnosing code U1729 involves checking the wiring connections between the control module and the headlamp motor, testing the components for proper functionality, and using a scan tool to retrieve specific error codes and data related to the communication problem.

4. Can a DIYer repair OBDII code U1729?

Repairing code U1729 may require advanced diagnostic equipment and knowledge of automotive electrical systems. It is recommended to consult a professional mechanic or technician to properly diagnose and repair the issue.

5. Is it safe to continue driving with OBDII code U1729 present?

Driving with code U1729 present can affect the functionality of your high beams and headlamp control, potentially compromising visibility at night or in poor weather conditions. It is advisable to address the issue promptly to ensure safe driving.

6. How much does it typically cost to repair OBDII code U1729?

The cost of repairing code U1729 can vary depending on the underlying cause of the communication problem. It may involve replacing wiring harnesses, control modules, or headlamp motors, so the cost can range from a few hundred dollars to over a thousand dollars.

7. Are there any preventive measures to avoid OBDII code U1729 in the future?

Regular maintenance checks, including inspecting the wiring connections, ensuring proper ground connections, and keeping the control modules clean and dry, can help prevent issues that may trigger code U1729.

8. Can extreme weather conditions contribute to triggering OBDII code U1729?

Extreme weather conditions such as heavy rain, snow, or extreme temperatures can potentially damage the wiring connections or components related to the high beam control module and headlamp motor, leading to communication problems and triggering code U1729.

9. How long does it usually take to repair OBDII code U1729?

The repair time for code U1729 can vary depending on the extent of the diagnosis needed and the availability of replacement parts. It may take a few hours to a full day for a skilled technician to diagnose and repair the issue.

10. Will resetting the OBDII system clear code U1729?

Resetting the OBDII system may temporarily clear the error code, but if the underlying issue causing code U1729 is not addressed, the code is likely to reappear. It is essential to diagnose and repair the root cause of the communication problem to prevent the code from returning.