AutoCodes – Buick – U1839 Buick

U1839 Buick Code - Auxiliary Transmission Fluid Pump Control Module Lost Communication With Engine Control Module

Quick Answer

The serial data circuit is the means by which the devices in the vehicle communicate with each other. Common causes include Faulty Engine Control Module (ECM), Engine Control Module harness is open or shorted, Engine 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: U1839 Buick indicates Auxiliary Transmission Fluid Pump Control Module Lost Communication With Engine Control Module.
Common causes: Common causes include Faulty Engine Control Module (ECM), Engine Control Module harness is open or shorted, Engine 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 647

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 07, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U1839 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 U1839 Buick - Auxiliary Transmission Fluid Pump Control Module Lost Communication With Engine Control Module - AutoCodes.com — U1839 Buick Code - Auxiliary Transmission Fluid Pump Control Module Lost Communication With Engine Control Module

What does this mean?

What are the Possible Causes of the DTC U1839 Buick?

Faulty Engine Control Module (ECM)
Engine Control Module harness is open or shorted
Engine Control Module circuit poor electrical connection

How to Fix the DTC U1839 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 U1839 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 U1839 Buick Code

1. What are common symptoms of OBDII code U1839 in a Buick related to the Auxiliary Transmission Fluid Pump Control Module?

- Common symptoms include transmission shifting issues, illuminated dashboard warning lights, and potential loss of communication between control modules.

2. What typically causes the U1839 code to trigger in a Buick?

- The U1839 code is usually triggered when there is a communication error between the Auxiliary Transmission Fluid Pump Control Module and the Engine Control Module.

3. How can I diagnose the U1839 code in my Buick?

- Diagnosing the U1839 code typically involves using an OBDII scanner to retrieve the code, checking for any related symptoms, and performing a thorough inspection of the transmission control modules.

4. Are there any simple repair tips for resolving the U1839 code in a Buick?

- Some simple repair tips for addressing the U1839 code may include checking and resetting the control module communication, inspecting wiring connections for any corrosion or damage, and ensuring proper power supply to the modules.

5. Can I drive my Buick with the U1839 code present?

- It is not recommended to drive your Buick with the U1839 code present, as it can lead to transmission performance issues and potential safety concerns. It is best to address the code promptly.

6. How much does it typically cost to repair the U1839 code in a Buick?

- The cost of repairing the U1839 code in a Buick can vary depending on the exact cause of the issue, but it may range from a simple wiring repair to a module replacement, potentially costing a few hundred to a few thousand dollars.

7. Will resetting the trouble codes clear the U1839 code from my Buick?

- Resetting the trouble codes may temporarily clear the U1839 code, but if the underlying issue causing the code is not addressed, it is likely to reappear. It is important to diagnose and repair the root cause of the problem.

8. Can a DIY enthusiast fix the U1839 code issue in a Buick?

- While some basic checks and repairs may be possible for a DIY enthusiast, diagnosing and repairing the U1839 code related to control module communication issues may require specialized tools and expertise best handled by a professional mechanic.

9. How urgent is it to address the U1839 code in a Buick?

- It is important to address the U1839 code promptly to prevent potential transmission malfunctions and ensure the overall safety and performance of your Buick.

10. Is the U1839 code specific to Buick vehicles only?

- The U1839 code related to Auxiliary Transmission Fluid Pump Control Module communication issues can be found in various Buick models, as well as in other vehicles that utilize similar control modules and communication systems.