AutoCodes – Buick – U18CC Buick

U18CC Buick Code - Transmission Range Control Module Lost Communication With ECM On Powertrain Expansion Bus

Quick Answer

Devices connected to the serial data circuits monitor for serial data communications during normal vehicle operation. 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: U18CC Buick indicates Transmission Range Control Module Lost Communication With ECM On Powertrain Expansion Bus.
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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 599

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 09, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code U18CC Buick 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. The Diagnostic Trouble Code (DTC) will set a supervised periodic message that includes the transmitter device availability that has not been received.

OBDII Code U18CC Buick - Transmission Range Control Module Lost Communication With ECM On Powertrain Expansion Bus - AutoCodes.com — U18CC Buick Code - Transmission Range Control Module Lost Communication With ECM On Powertrain Expansion Bus

What does this mean?

What are the Possible Causes of the DTC U18CC 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 U18CC 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 U18CC 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 U18CC Buick code?

Need more information on how to fix the U18CC Buick code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U18CC Buick code diagnosed by a professional: Find a repair shop in your area

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 U18CC Buick Code

1. What are common symptoms of OBDII code U18CC in a Buick related to the Transmission Range Control Module losing communication with the ECM?

- Common symptoms include transmission shifting issues, stalling, poor vehicle performance, and illuminated warning lights on the dashboard.

2. What are possible causes of the U18CC OBDII code in a Buick?

- Possible causes include a faulty Transmission Range Control Module, damaged wiring or connectors, a malfunctioning ECM, or a communication bus fault.

3. How can I diagnose the U18CC code in my Buick?

- Diagnosis typically involves using a professional OBDII scanner to retrieve the code and then performing a thorough inspection of the transmission control system, wiring, connectors, and communication modules.

4. How can I repair the U18CC OBDII code in my Buick?

- Repair options may include replacing the faulty Transmission Range Control Module, repairing damaged wiring or connectors, reprogramming the ECM, or addressing any communication bus faults.

5. Is it safe to continue driving my Buick with the U18CC code present?

- It is not recommended to continue driving your Buick with the U18CC code present, as it can lead to further transmission issues and potential safety hazards. It is best to address the problem promptly.

6. Can a DIY enthusiast fix the U18CC code issue in a Buick?

- While some aspects of diagnosing and repairing the U18CC code may be possible for experienced DIY enthusiasts, it is recommended to consult with a professional mechanic or dealership for accurate diagnosis and repair.

7. How much does it typically cost to repair the U18CC code in a Buick?

- The cost of repairing the U18CC code can vary depending on the specific cause of the issue, parts needed for replacement, and labor costs. It is advisable to obtain estimates from reputable mechanics or dealerships.

8. Are there any preventive maintenance steps to avoid the U18CC code in a Buick?

- Regularly servicing your vehicle, addressing any transmission-related issues promptly, and ensuring proper electrical system maintenance can help reduce the risk of encountering the U18CC code.

9. Can extreme weather conditions affect the occurrence of the U18CC code in a Buick?

- Extreme weather conditions can potentially impact the electrical connections and components related to the transmission control system, which may contribute to the occurrence of the U18CC code.