AutoCodes – Generic – U2125

U2125 Code - Lost Communication With Telematic Unit

Quick Answer

Devices connected to the serial data circuits monitor for serial data communications during normal vehicle operation. Common causes include Faulty Telematic Unit, Telematic Unit harness is open or shorted, Telematic Unit 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: U2125 indicates Lost Communication With Telematic Unit.
Common causes: Common causes include Faulty Telematic Unit, Telematic Unit harness is open or shorted, Telematic Unit 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 4,904

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 16, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U2125 Description

Devices connected to the serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the devices. The devices have prerecorded information about what messages are needed to be exchanged on the serial data circuits, for each virtual network. The messages are supervised and also, some periodic messages are used by the receiver device as an availability indication of the transmitter device. Each message contains the identification number of the transmitter device. A loss of serial data communications Diagnostic Trouble Code (DTC) does not represent a failure of the devices that contain the stored code. The DTC will set when a supervised periodic message that includes the transmitter device availability has not been received.

OBDII Code U2125 - Lost Communication With Telematic Unit - AutoCodes.com — U2125 Code - Lost Communication With Telematic Unit

What does this mean?

What are the Possible Causes of the DTC U2125?

Faulty Telematic Unit
Telematic Unit harness is open or shorted
Telematic Unit circuit poor electrical connection

How to Fix the DTC U2125?

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 U2125 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 U2125 code?

Need more information on how to fix the U2125 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U2125 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

U2125 Buick — Lost Communication With Telematic Unit
U2125 Cadillac — Lost Communication With Telematic Unit
U2125 Chevrolet — Lost Communication With Telematic Unit
U2125 GMC — Lost Communication With Telematic Unit
U2125 Saturn — Lost Communication With Telematic Unit

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 U2125 Code

1. What are the common symptoms of OBDII code U2125 (Lost Communication With Telematic Unit)?

- Common symptoms include the malfunction indicator light (MIL) coming on, loss of communication with the telematic unit, and potential issues with telematics features in the vehicle.

2. What are some possible causes of OBDII code U2125?

- Possible causes may include a faulty telematic unit, wiring or connection issues between the telematic unit and the vehicle's computer, or a software glitch in the telematics system.

3. How can I diagnose the cause of OBDII code U2125?

- Diagnosing the cause typically involves checking the connections to the telematic unit, inspecting the wiring for any damage, and using a diagnostic scan tool to communicate with the telematic unit.

4. Can OBDII code U2125 be repaired without professional help?

- Simple issues like loose connections or corroded wiring may be repaired without professional help, but diagnosing and repairing more complex issues with the telematic unit itself may require professional assistance.

5. Are there any temporary fixes for OBDII code U2125?

- In some cases, simply disconnecting the battery for a few minutes to reset the vehicle's computer may temporarily clear the code, but it is important to diagnose and address the root cause for a permanent fix.

6. Will OBDII code U2125 prevent my vehicle from starting?

- In most cases, this code should not prevent the vehicle from starting, but it may affect the functionality of certain telematics features and could lead to other issues if left unresolved.

7. How much does it typically cost to repair OBDII code U2125?

- The cost of repairing this code can vary depending on the underlying cause. Simple fixes like reconnecting loose wires may be inexpensive, while replacing a faulty telematic unit could be more costly.

8. Can driving with OBDII code U2125 cause further damage to the vehicle?

- While driving with this code may not directly cause damage, unresolved communication issues with the telematic unit could potentially lead to other electrical problems in the vehicle over time.

9. Is it safe to continue driving with OBDII code U2125 present?

- It is generally safe to drive with this code present, but it is recommended to have the issue diagnosed and repaired as soon as possible to ensure the proper functioning of the telematics system.

10. How long does it typically take to repair OBDII code U2125?

- The repair time can vary based on the complexity of the issue. Simple fixes may only take a short amount of time, while more involved repairs could require leaving the vehicle with a mechanic for a day or more.