AutoCodes – Cadillac – U1889 Cadillac

U1889 Cadillac Code - Hybrid Control Module Lost Communication With Body Control Module

Quick Answer

Modules connected to the class 2 and high-speed General Motor Local Area Network (GMLAN) serial data circuits monitor for serial data communications during normal vehicle operation. Common causes include Faulty Body Control Module (BCM), Body Control Module harness is open or shorted, Body 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: U1889 Cadillac indicates Hybrid Control Module Lost Communication With Body Control Module.
Common causes: Common causes include Faulty Body Control Module (BCM), Body Control Module harness is open or shorted, Body 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 424

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 08, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U1889 Cadillac Description

Modules connected to the class 2 and high-speed General Motor Local Area Network (GMLAN) serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. The Diagnostic Trouble Code (DTC) is reported on a class 2 link to the scan tool by Powertrain Control Module (PCM) even if they may be set by different modules. The DTC will set when a node alive message has not been received from an identified module within the last 5 seconds after establishing class 2 serial data communication, or a supervised high-speed GMLAN message has not been received.

OBDII Code U1889 Cadillac - Hybrid Control Module Lost Communication With Body Control Module - AutoCodes.com — U1889 Cadillac Code - Hybrid Control Module Lost Communication With Body Control Module

What does this mean?

What are the Possible Causes of the DTC U1889 Cadillac?

Faulty Body Control Module (BCM)
Body Control Module harness is open or shorted
Body Control Module circuit poor electrical connection
Faulty Hybrid Control Module (HCM)

How to Fix the DTC U1889 Cadillac?

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 U1889 Cadillac 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 U1889 Cadillac Code

1. What are common symptoms of OBDII code U1889 in a Cadillac hybrid?

Symptoms may include loss of communication between the hybrid control module and body control module, warning lights on the dashboard, issues with hybrid system operation, and possible performance issues.

2. What can cause the U1889 code in a Cadillac hybrid?

The U1889 code is typically triggered when there is a communication error between the hybrid control module and body control module. This can be caused by wiring issues, faulty modules, software glitches, or other electrical problems.

3. How can I diagnose the U1889 code in my Cadillac hybrid?

Diagnosing the U1889 code usually involves using a professional OBDII scanner to retrieve the code, checking the wiring and connectors between the hybrid control module and body control module, and performing a thorough inspection of the electrical system.

4. Can I still drive my Cadillac hybrid with the U1889 code?

It is not recommended to drive your Cadillac hybrid with the U1889 code present, as it can affect the proper functioning of the hybrid system. It is best to have the issue diagnosed and repaired as soon as possible.

5. How can I repair the U1889 code in my Cadillac hybrid?

Repairing the U1889 code may involve fixing any wiring or connector issues, replacing faulty modules, updating software if needed, and ensuring proper communication between the hybrid control module and body control module.

6. Is the U1889 code a serious issue in a Cadillac hybrid?

While the U1889 code may not always indicate a critical problem, it can lead to performance issues and affect the operation of the hybrid system. It is important to address the issue promptly to prevent further complications.

7. Can I reset the U1889 code in my Cadillac hybrid?

Resetting the U1889 code may temporarily clear the warning lights, but if the underlying issue is not addressed, the code is likely to reappear. It is best to diagnose and repair the root cause of the problem.

8. How much does it cost to fix the U1889 code in a Cadillac hybrid?

The cost of fixing the U1889 code can vary depending on the specific issue causing the communication error. It is recommended to consult a professional mechanic for an accurate diagnosis and cost estimate.

9. Will the U1889 code affect the fuel efficiency of my Cadillac hybrid?

If left unresolved, the U1889 code can potentially impact the fuel efficiency of your Cadillac hybrid due to issues with the hybrid system operation. Addressing the problem promptly can help maintain optimal fuel efficiency.

10. How can I prevent the U1889 code from recurring in my Cadillac hybrid?

Regular maintenance, including checking the wiring and connectors, keeping software up to date, and addressing any electrical issues promptly, can help prevent the U1889 code from recurring in your Cadillac hybrid.