AutoCodes – GMC – U155D GMC

U155D GMC Code - Body Control Module Lost Communication With Right Rear Seat Heating/Venting/Cooling Switch On LIN Bus

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 Rear Seat Heating/Venting/Cooling Switch, Right Rear Seat Heating/Venting/Cooling Switch harness is open or shorted, Right Rear Seat Heating/Venting/Cooling 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: U155D GMC indicates Body Control Module Lost Communication With Right Rear Seat Heating/Venting/Cooling Switch On LIN Bus.
Common causes: Common causes include Faulty Right Rear Seat Heating/Venting/Cooling Switch, Right Rear Seat Heating/Venting/Cooling Switch harness is open or shorted, Right Rear Seat Heating/Venting/Cooling 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 498

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

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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 U155D 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 Body Control Module (BCM) from the Right Rear Seat Heating/Venting/Cooling Switch has not been received.

OBDII Code U155D GMC - Body Control Module Lost Communication With Right Rear Seat Heating/Venting/Cooling Switch On LIN Bus - AutoCodes.com — U155D GMC Code - Body Control Module Lost Communication With Right Rear Seat Heating/Venting/Cooling Switch On LIN Bus

What does this mean?

What are the Possible Causes of the DTC U155D GMC?

Faulty Right Rear Seat Heating/Venting/Cooling Switch
Right Rear Seat Heating/Venting/Cooling Switch harness is open or shorted
Right Rear Seat Heating/Venting/Cooling Switch circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC U155D 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 U155D 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.

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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 U155D GMC Code

1. What are the common symptoms of OBDII code U155D in a GMC vehicle?

- Common symptoms include malfunctioning right rear seat heating, venting, or cooling system, loss of communication with the switch, and illuminated warning lights on the dashboard.

2. What does the OBDII code U155D GMC indicate?

- The code U155D indicates that the Body Control Module has lost communication with the right rear seat heating/venting/cooling switch on the LIN bus.

3. What are the possible causes of the U155D code in a GMC vehicle?

- Possible causes include a faulty right rear seat heating/venting/cooling switch, damaged wiring or connectors, a malfunctioning Body Control Module, or communication bus issues.

4. How can I diagnose the U155D code in my GMC vehicle?

- Diagnosis involves inspecting the wiring and connectors related to the right rear seat switch, testing the switch itself for functionality, checking the Body Control Module for any faults, and scanning the LIN bus for communication issues.

5. What are some repair tips for resolving the U155D code in a GMC vehicle?

- Repair tips include repairing or replacing damaged wiring and connectors, replacing the faulty right rear seat switch if necessary, reprogramming or replacing the Body Control Module, and ensuring proper communication on the LIN bus.

6. Can the U155D code be cleared/reset without fixing the underlying issue?

- Clearing the code without addressing the root cause may temporarily turn off the warning light, but the issue will persist and the code is likely to return.

7. Is it safe to drive with the U155D code present in a GMC vehicle?

- It is generally safe to drive with this code, but the right rear seat heating/venting/cooling system may not function properly until the issue is resolved.

8. Can a DIY enthusiast fix the U155D code issue in a GMC vehicle?

- Depending on the specific cause, DIY enthusiasts with automotive repair experience may be able to address the issue by following diagnostic procedures and repair tips.

9. How much does it typically cost to repair the U155D code in a GMC vehicle?

- Repair costs can vary widely depending on the cause of the issue, but they may range from a few hundred to over a thousand dollars if professional diagnostic and repair services are required.

10. Will the U155D code cause any long-term damage to the vehicle if left unresolved?

- Leaving the issue unresolved may lead to continued malfunction of the right rear seat heating/venting/cooling system, but it is unlikely to cause significant long-term damage to the vehicle.