AutoCodes – GMC – U184B GMC

U184B GMC Code - Lost Communication with Remote Heater and Air Conditioning Control Module on Low Speed CAN Bus

Quick Answer

The serial data circuit is the means by which the devices in the vehicle communicate with each other. Common causes include Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module, Heating, Ventilation, and Air Conditioning Control Module harness is open or shorted, Heating, Ventilation, and Air Conditioning Control Module 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: U184B GMC indicates Lost Communication with Remote Heater and Air Conditioning Control Module on Low Speed CAN Bus.
Common causes: Common causes include Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module, Heating, Ventilation, and Air Conditioning Control Module harness is open or shorted, Heating, Ventilation, and Air Conditioning Control Module 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 576

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 Aug 09, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U184B GMC Description

The serial data circuit is the means by which the devices in the vehicle communicate with each other. Once the scan tool is connected to the serial data circuit through the Data Link Connector (DLC), the scan tool can be used to monitor each device for diagnostic purposes and to check for Diagnostic Trouble Codes (DTC). When the vehicle is ON, each device communicating on the serial data circuit sends a state of health message to ensure that the device is operating properly. When a device stops communicating on the serial data circuit, for example, if the device loses power or ground, the state of health message it normally sends on the serial data circuit disappears. Other devices on the serial data circuit, which expect to receive that state of health message, detect its absence; those devices in turn set a DTC associated with the loss of state of health of the non-communicating device. A loss of serial data communications DTC does not represent a failure of the devices that contain the stored DTC.

OBDII Code U184B GMC - Lost Communication with Remote Heater and Air Conditioning Control Module on Low Speed CAN Bus - AutoCodes.com — U184B GMC Code - Lost Communication with Remote Heater and Air Conditioning Control Module on Low Speed CAN Bus

What does this mean?

What are the Possible Causes of the DTC U184B GMC?

Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module
Heating, Ventilation, and Air Conditioning Control Module harness is open or shorted
Heating, Ventilation, and Air Conditioning Control Module circuit poor electrical connection

How to Fix the DTC U184B 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 U184B 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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Information for Specific GMC Models

U184B 2014 GMC Sierra — Lost Communication with Remote Heater and Air Conditioning Control Module on Low Speed CAN Bus
U184B 2015 GMC Sierra — Lost Communication with Remote Heater and Air Conditioning Control Module on Low Speed CAN Bus
U184B 2016 GMC Sierra — Lost Communication with Remote Heater and Air Conditioning Control Module on Low Speed CAN Bus
U184B 2017 GMC Sierra — Lost Communication with Remote Heater and Air Conditioning Control Module on Low Speed CAN Bus
U184B 2018 GMC Sierra — Lost Communication with Remote Heater and Air Conditioning Control Module on Low Speed CAN Bus

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 U184B GMC Code

1. What are common symptoms of OBDII code U184B GMC?

- Common symptoms include loss of communication with the remote heater and air conditioning control module, inoperative heater or air conditioning system, and dashboard warning lights.

2. What can cause the OBDII code U184B GMC to appear?

- The code may appear due to issues such as damaged wiring, a faulty control module, poor electrical connections, or a malfunctioning CAN bus system.

3. How can I diagnose the cause of the U184B GMC code?

- Diagnose the code by checking the wiring and connections related to the remote heater and air conditioning control module, testing the module itself, and using a diagnostic scanner to assess the CAN bus communication.

4. What are some repair tips for resolving the U184B GMC trouble code?

- Repair tips include repairing or replacing damaged wiring, ensuring proper electrical connections, replacing the remote heater and air conditioning control module if needed, and addressing any underlying CAN bus issues.

5. Can the U184B GMC code be cleared/reset without fixing the underlying issue?

- While clearing the code may temporarily turn off the warning light, it is important to address the underlying issue causing the code to prevent further problems with the heater and air conditioning system.

6. Is it safe to continue driving with the U184B GMC trouble code present?

- It is not recommended to drive with the U184B code present, as it may indicate a potential issue with the heater and air conditioning system, which can affect comfort and safety while driving.

7. How much does it typically cost to repair the U184B GMC code?

- The cost of repairing the U184B code can vary depending on the specific issue, but it may involve expenses such as parts replacement, labor costs, and diagnostic fees.

8. Can I fix the U184B GMC code myself, or do I need a professional mechanic?

- Depending on your automotive repair skills and knowledge, you may be able to address the U184B code yourself by following repair guides and using diagnostic tools. However, complex issues may require the expertise of a professional mechanic.

9. Will the U184B GMC trouble code cause my vehicle to fail an emissions test?

- The U184B code itself may not directly cause the vehicle to fail an emissions test, but unresolved issues related to the heater and air conditioning system can impact overall vehicle performance and emissions.

10. How can I prevent the U184B GMC code from reoccurring in the future?

- To prevent the U184B code from reoccurring, regularly inspect and maintain the electrical system, ensure proper connections, address any warning lights promptly, and follow recommended maintenance schedules for your vehicle.