AutoCodes – Buick – U1838 Buick

U1838 Buick Code - Lost Communication With Battery Charger Control Module On High Voltage Energy Management 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 Battery Charger Control Module, Battery Charger Control Module harness is open or shorted, Battery Charger 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: U1838 Buick indicates Lost Communication With Battery Charger Control Module On High Voltage Energy Management CAN Bus.
Common causes: Common causes include Faulty Battery Charger Control Module, Battery Charger Control Module harness is open or shorted, Battery Charger 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 627

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 U1838 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 U1838 Buick - Lost Communication With Battery Charger Control Module On High Voltage Energy Management CAN Bus - AutoCodes.com — U1838 Buick Code - Lost Communication With Battery Charger Control Module On High Voltage Energy Management CAN Bus

What does this mean?

What are the Possible Causes of the DTC U1838 Buick?

Faulty Battery Charger Control Module
Battery Charger Control Module harness is open or shorted
Battery Charger Control Module circuit poor electrical connection

How to Fix the DTC U1838 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 U1838 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 U1838 Buick Code

1. What are common symptoms of OBDII code U1838 in a Buick?

- Common symptoms include the Check Engine light illuminating, loss of communication with the battery charger control module, and potential issues with the high voltage energy management system.

2. What can cause the OBDII code U1838 to be triggered in a Buick?

- This code is typically triggered when there is a communication breakdown between the vehicle's onboard diagnostic system and the battery charger control module on the high voltage energy management CAN bus.

3. How serious is the U1838 code in a Buick?

- While the code itself may not cause immediate drivability issues, it is important to address it promptly to ensure the proper functioning of the high voltage energy management system in the vehicle.

4. How can I diagnose the U1838 code in my Buick?

- Diagnosing this code usually involves using a professional OBDII scanner to retrieve the specific fault codes, checking the wiring and connections related to the battery charger control module, and verifying the communication signals on the high voltage energy management CAN bus.

5. Can I repair the U1838 code in my Buick myself?

- Depending on your experience and access to tools, you may be able to address this code yourself by checking and repairing any loose connections, damaged wiring, or faulty components related to the battery charger control module and the high voltage energy management system.

6. Is it safe to continue driving with the U1838 code present in my Buick?

- While the vehicle may still be operable with this code present, it is recommended to address the underlying issue as soon as possible to prevent potential long-term damage to the high voltage energy management system.

7. Can weather conditions affect the triggering of the U1838 code in a Buick?

- Extreme weather conditions, such as temperature fluctuations or moisture exposure, can sometimes impact the communication between the battery charger control module and the vehicle's diagnostic system, potentially leading to the triggering of this code.

8. What are some potential repair tips for the U1838 code in a Buick?

- Some repair tips include checking and securing all connections, inspecting the wiring harness for any damage, ensuring proper grounding, and resetting the fault codes after any repairs are made.

9. Are there any recalls or technical service bulletins related to the U1838 code in Buick vehicles?

- It is recommended to check with the manufacturer or authorized dealerships for any relevant recalls or technical service bulletins that may provide additional guidance or support for addressing the U1838 code in Buick vehicles.

10. How much does it typically cost to repair the U1838 code in a Buick?

- The cost of repairing the U1838 code can vary depending on the underlying issue, the extent of repairs needed, and labor rates in your area. It is advisable to get estimates from reputable mechanics or dealerships for an accurate cost assessment.