AutoCodes – Buick – U1831 Buick

U1831 Buick Code - Drive Motor Control Module 1 Lost Communication With Hybrid/EV Powertrain Control Module On Powertrain Expansion 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 Hybrid/EV Powertrain Control Module, Hybrid/EV Powertrain Control Module harness is open or shorted, Hybrid/EV Powertrain 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: U1831 Buick indicates Drive Motor Control Module 1 Lost Communication With Hybrid/EV Powertrain Control Module On Powertrain Expansion CAN Bus.
Common causes: Common causes include Faulty Hybrid/EV Powertrain Control Module, Hybrid/EV Powertrain Control Module harness is open or shorted, Hybrid/EV Powertrain 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 542

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 07, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U1831 Buick 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 Code (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 the health message, detect its absence; those devices in turn set a DTC associated with the loss of the 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. The DTC will set when a supervised periodic message that includes the transmitter device availability has not been received.

OBDII Code U1831 Buick - Drive Motor Control Module 1 Lost Communication With Hybrid/EV Powertrain Control Module On Powertrain Expansion CAN Bus - AutoCodes.com — U1831 Buick Code - Drive Motor Control Module 1 Lost Communication With Hybrid/EV Powertrain Control Module On Powertrain Expansion CAN Bus

What does this mean?

What are the Possible Causes of the DTC U1831 Buick?

Faulty Hybrid/EV Powertrain Control Module
Hybrid/EV Powertrain Control Module harness is open or shorted
Hybrid/EV Powertrain Control Module circuit poor electrical connection

How to Fix the DTC U1831 Buick?

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 U1831 Buick 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 U1831 Buick Code

1. What does the OBDII code U1831 mean on a Buick?

The U1831 code indicates that the Drive Motor Control Module 1 has lost communication with the Hybrid/EV Powertrain Control Module over the Powertrain Expansion CAN Bus.

2. What are common symptoms of the U1831 code in a Buick?

Common symptoms include the illumination of the check engine light, reduced power mode, poor driving performance, or a failure to start the vehicle.

3. What causes the U1831 code on a Buick?

The U1831 code can be caused by faulty wiring, loose or damaged CAN bus connections, a failing Drive Motor Control Module, or issues with the Hybrid/EV Powertrain Control Module.

4. Can a dead battery cause the U1831 code to appear?

Yes, a weak or dead 12V battery or high-voltage battery can disrupt communication between modules and trigger the U1831 code.

5. How is the U1831 code diagnosed?

Technicians diagnose the U1831 code by using a scan tool to check for additional codes, inspecting CAN bus wiring and connections, and testing the operation of the involved control modules.

6. Can I drive my Buick with the U1831 code active?

It is not recommended to drive with the U1831 code active, as it may cause reduced power or other operational issues, potentially leading to unsafe driving conditions.

7. How do you fix the U1831 code on a Buick?

Fixing the U1831 code involves repairing or replacing damaged wiring or connectors, updating or reprogramming the affected modules, or replacing a faulty Drive Motor Control or Powertrain Control Module.

8. Is the U1831 code specific to hybrid or EV Buicks?

Yes, the U1831 code is specific to hybrid or electric vehicles, as it pertains to communication between the Drive Motor Control Module and the Hybrid/EV Powertrain Control Module.

9. Can a software update resolve the U1831 code on a Buick?

In some cases, a software update or reprogramming of the affected modules may resolve the U1831 code if it is caused by a firmware compatibility issue.

10. How much does it cost to repair the U1831 code on a Buick?

The repair cost for the U1831 code can vary widely, ranging from $100 for simple wiring repairs to over $1,000 if a module replacement or reprogramming is required.