AutoCodes – Buick – U0402 Buick

U0402 Buick Code - Invalid Data Received From Transmission Control Module

Quick Answer

A Controller Area Network (CAN) is a vehicle bus standard designed to interconnect automotive devices without a host computer. Common causes include Faulty Transmission Control Module (TCM), Transmission Control Module harness is open or shorted, Transmission 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: U0402 Buick indicates Invalid Data Received From Transmission Control Module.
Common causes: Common causes include Faulty Transmission Control Module (TCM), Transmission Control Module harness is open or shorted, Transmission 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 965

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 Apr 08, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U0402 Buick Description

A Controller Area Network (CAN) is a vehicle bus standard designed to interconnect automotive devices without a host computer. Operating information and commands are exchanged among the devices. The devices have programmed information about what messages are needed to be exchanged on the serial data circuits. Some devices are constantly receiving information from other devices through serial data communication network. The invalid data Diagnostic Trouble Code (DTC) will be set when a receiving device detects a discrepancy in the information it receives from the Transmission Control Module (TCM) causing its integrity to be questioned.

OBDII Code U0402 Buick - Invalid Data Received From Transmission Control Module - AutoCodes.com — U0402 Buick Code - Invalid Data Received From Transmission Control Module

What does this mean?

What are the Possible Causes of the DTC U0402 Buick?

Faulty Transmission Control Module (TCM)
Transmission Control Module harness is open or shorted
Transmission Control Module circuit poor electrical connection

How to Fix the DTC U0402 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 U0402 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.

Need more information about the U0402 Buick code?

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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 U0402 Buick Code

1. What are common symptoms of OBDII code U0402 in a Buick related to the Transmission Control Module?

- Common symptoms include erratic shifting, transmission slipping, and the transmission going into limp mode.

2. What can cause the OBDII code U0402 "Invalid Data Received From Transmission Control Module" in a Buick?

- This code can be triggered by issues such as a faulty Transmission Control Module, damaged wiring, or a communication error between modules.

3. How can I diagnose the OBDII code U0402 in my Buick?

- Diagnosis typically involves using a professional OBDII scanner to retrieve the code, checking the transmission control module for any visible damage, and inspecting the wiring for any breaks or corrosion.

4. Is it safe to continue driving my Buick with the U0402 OBDII code?

- It is not recommended to continue driving the vehicle with this code present, as it can lead to further transmission damage and potential safety hazards.

5. Can I reset the U0402 code in my Buick by disconnecting the battery?

- While disconnecting the battery may temporarily clear the code, it is important to address the underlying issue causing the code to prevent it from reoccurring.

6. How much does it typically cost to repair the U0402 code in a Buick?

- The cost of repair can vary depending on the specific issue causing the code, but it may involve replacing the Transmission Control Module, repairing wiring, or addressing communication errors, which can range from a few hundred to over a thousand dollars.

7. Are there any DIY repair tips for the U0402 OBDII code in a Buick?

- DIY repairs for this code are not recommended due to the complexity of transmission control systems. It is best to consult a professional mechanic for proper diagnosis and repair.

8. Can a software update fix the U0402 code in my Buick?

- In some cases, a software update from the manufacturer may address communication issues causing the code. Consult with a dealership or qualified mechanic to determine if this is a viable solution for your vehicle.

9. Will the U0402 code cause my Buick to fail an emissions test?

- Yes, the U0402 code can cause your vehicle to fail an emissions test due to the impact on the transmission system, which is essential for proper vehicle operation and emissions control.

10. How long does it typically take to repair the U0402 code in a Buick?

- The repair time can vary depending on the specific issue causing the code and the availability of parts. It may take anywhere from a few hours to a day or more to properly diagnose and repair the U0402 code.