AutoCodes – GMC – U1727 GMC

U1727 GMC Code - Right Headlamp High Beam Control Module Lost Communication With Right Headlamp Leveling Actuator

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 Leveling Actuator, Right Headlamp Leveling Actuator harness is open or shorted, Right Headlamp Leveling Actuator 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: U1727 GMC indicates Right Headlamp High Beam Control Module Lost Communication With Right Headlamp Leveling Actuator.
Common causes: Common causes include Faulty Right Headlamp Leveling Actuator, Right Headlamp Leveling Actuator harness is open or shorted, Right Headlamp Leveling Actuator 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 581

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 04, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U1727 GMC 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 Headlamp High Beam Control Module from the Right Headlamp Leveling Actuator has not been received.

OBDII Code U1727 GMC - Right Headlamp High Beam Control Module Lost Communication With Right Headlamp Leveling Actuator - AutoCodes.com — U1727 GMC Code - Right Headlamp High Beam Control Module Lost Communication With Right Headlamp Leveling Actuator

What does this mean?

What are the Possible Causes of the DTC U1727 GMC?

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

How to Fix the DTC U1727 GMC?

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 U1727 GMC 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 U1727 GMC code?

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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 U1727 GMC Code

1. What are common symptoms of OBDII code U1727 in a GMC vehicle?

- Common symptoms include the right headlamp high beam not functioning properly, uneven headlight alignment, and potentially a warning light on the dashboard.

2. What causes the U1727 code to trigger in a GMC vehicle?

- The U1727 code is triggered when there is a communication failure between the right headlamp high beam control module and the right headlamp leveling actuator.

3. How can I diagnose the U1727 code in my GMC vehicle?

- Diagnosis typically involves using a diagnostic scanner to retrieve the code, checking the wiring and connections between the control module and actuator, and testing the components for proper functioning.

4. Can a DIY enthusiast repair the U1727 code in a GMC vehicle?

- While some basic troubleshooting steps can be performed by DIY enthusiasts, repairing the communication issue between the control module and actuator may require specialized tools and expertise.

5. Is it safe to drive with the U1727 code present in a GMC vehicle?

- It is generally safe to drive with the U1727 code, but it is recommended to address the issue promptly to ensure proper functionality of the right headlamp high beam and leveling system.

6. How much does it typically cost to repair the U1727 code in a GMC vehicle?

- The cost of repairing the U1727 code can vary depending on the underlying cause, but it may involve replacing faulty components, which could range from a few hundred to a few thousand dollars.

7. Can the U1727 code be intermittent or is it usually a persistent issue?

- The U1727 code can be intermittent in some cases, especially if the communication failure between the control module and actuator is due to loose connections or wiring issues.

8. Are there any preventive measures to avoid the U1727 code in a GMC vehicle?

- Keeping the headlamp components clean and well-maintained, and addressing any electrical issues promptly, can help prevent the U1727 code from occurring.

9. Will resetting the trouble codes make the U1727 code disappear permanently?

- Resetting the trouble codes may temporarily clear the U1727 code, but if the underlying communication issue is not addressed, the code is likely to reappear.

10. Can the U1727 code affect other vehicle systems in addition to the headlamp control module?

- The U1727 code specifically relates to the communication between the headlamp components, so it may not directly affect other vehicle systems, but addressing the issue promptly is still important for overall vehicle safety.