AutoCodes – GMC – U184B 2018 GMC Sierra

U184B 2018 GMC Sierra 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 2018 GMC Sierra 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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 177

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 Jul 24, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code U184B 2018 GMC Sierra 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 2018 GMC Sierra - Lost Communication with Remote Heater and Air Conditioning Control Module on Low Speed CAN Bus - AutoCodes.com — U184B 2018 GMC Sierra 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 2018 GMC Sierra?

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 2018 GMC Sierra?

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 2018 GMC Sierra 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 U184B 2018 GMC Sierra code?

Need more information on how to fix the U184B 2018 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U184B 2018 GMC Sierra code diagnosed by a professional: Find a repair shop in your area

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 2018 GMC Sierra Code

1. What are the common symptoms of OBDII code U184B in a 2018 GMC Sierra related to "Lost Communication with Remote Heater and Air Conditioning Control Module on Low Speed CAN Bus"?

- Common symptoms include issues with the remote heater and air conditioning control, loss of climate control functionality, and warning lights on the dashboard.

2. What are the possible causes of U184B code in a 2018 GMC Sierra?

- Possible causes may include damaged wiring or connectors, a faulty remote heater and air conditioning control module, issues with the low-speed CAN bus communication, or a malfunctioning control module.

3. How can I diagnose the U184B code in my 2018 GMC Sierra?

- Diagnosis involves checking the wiring and connectors for damage, testing the remote heater and air conditioning control module, verifying the low-speed CAN bus communication, and using a diagnostic scan tool to pinpoint the issue.

4. Is it safe to continue driving my 2018 GMC Sierra with the U184B code?

- It is not recommended to drive the vehicle with the U184B code, as it can impact the operation of the remote heater and air conditioning system, potentially leading to discomfort or safety concerns.

5. Can I repair the U184B code in my 2018 GMC Sierra myself?

- While some basic checks like inspecting wiring and connectors can be done by DIY enthusiasts, diagnosing and repairing the specific issue related to the lost communication with the remote heater and air conditioning control module may require professional assistance.

6. How much does it typically cost to repair the U184B code in a 2018 GMC Sierra?

- The cost of repair can vary depending on the exact cause of the issue. It may involve replacing wiring, connectors, the control module, or addressing communication problems, so repair costs can range from a few hundred to over a thousand dollars.

7. Can a simple reset of the system clear the U184B code in a 2018 GMC Sierra?

- A simple system reset may temporarily clear the code, but if the underlying issue causing the lost communication with the remote heater and air conditioning control module is not addressed, the code is likely to reappear.

8. Are there any preventive maintenance tips to avoid encountering the U184B code in a 2018 GMC Sierra?

- Regularly inspecting the wiring and connectors for signs of wear or damage, as well as keeping the climate control system well-maintained, can help prevent issues that may trigger the U184B code.

9. How long does it typically take to repair the U184B code in a 2018 GMC Sierra?

- The repair time can vary depending on the exact cause of the issue and the complexity of the repair needed. It may take a few hours to a full day for diagnosis and repair to be completed.

10. Can the U184B code affect other systems in a 2018 GMC Sierra?

- While the U184B code specifically relates to the lost communication with the remote heater and air conditioning control module, it can impact the overall functionality of the climate control system and potentially affect other related systems in the vehicle.