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U179D Cadillac Code - Lost Communication With Brake System Control Module 2 On Chassis Expansion Bus

Quick Answer

The Local Interconnect Network (LIN) Bus consists of a single wire with a transmission rate of 10.417 Kbit/s. Common causes include Faulty Brake System Control Module 2, Brake System Control Module 2 harness is open or shorted, Brake System Control Module 2 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: U179D Cadillac indicates Lost Communication With Brake System Control Module 2 On Chassis Expansion Bus.
Common causes: Common causes include Faulty Brake System Control Module 2, Brake System Control Module 2 harness is open or shorted, Brake System Control Module 2 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 479

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

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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 U179D Cadillac Description

The Local Interconnect Network (LIN) Bus consists of a single wire with a transmission rate of 10.417 Kbit/s. The serial data is transmitted over a LIN circuit between a master control module and other LIN devices within a particular subsystem. If serial data communication is lost between any of the LIN devices on the LIN bus network, the master control module will set a no communication code against the non-communicating LIN device. The Diagnostic Trouble Code (DTC) will set when a supervised periodic message from the Brake System Control Module 2 has not been received.

OBDII Code U179D Cadillac - Lost Communication With Brake System Control Module 2 On Chassis Expansion Bus - AutoCodes.com — U179D Cadillac Code - Lost Communication With Brake System Control Module 2 On Chassis Expansion Bus

What does this mean?

What are the Possible Causes of the DTC U179D Cadillac?

Faulty Brake System Control Module 2
Brake System Control Module 2 harness is open or shorted
Brake System Control Module 2 circuit poor electrical connection

How to Fix the DTC U179D 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 U179D 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 U179D Cadillac Code

1. What does the OBDII code U179D mean for a Cadillac?

U179D indicates a loss of communication with the Brake System Control Module 2 on the chassis expansion bus, meaning the vehicle's network is unable to communicate with this module.

2. What are common symptoms of the U179D code?

Symptoms may include illuminated warning lights such as ABS, traction control, or stability control, as well as potential loss of brake-related features like anti-lock braking.

3. What causes the U179D code to appear?

Causes can include a faulty Brake System Control Module 2, damaged wiring or connectors, network communication issues, or a malfunction in another related module.

4. Can I drive with the U179D code active?

While the car may still be drivable, critical braking or stability control systems may not function properly, posing safety risks. Itâ€™s best to address the issue promptly.

5. How can I diagnose the U179D code?

Start by scanning the vehicle with a diagnostic tool to confirm the code. Then, inspect the wiring, connectors, and modules involved in the chassis expansion bus for damage or faults.

6. What should I check first when troubleshooting U179D?

Begin with a visual inspection of the wiring and connectors for corrosion, damage, or loose connections near the Brake System Control Module 2 and related components.

7. Does a U179D code always mean the Brake System Control Module 2 is faulty?

No, the issue could also stem from communication failures, wiring problems, or faults in other modules within the chassis expansion bus.

8. How is the U179D code repaired?

Repairs may involve replacing or repairing damaged wiring, cleaning or reconnecting corroded connectors, reprogramming the module, or replacing a faulty Brake System Control Module 2.

9. Can a low battery cause the U179D code?

Yes, a weak or discharged battery can cause communication errors in the vehicle's network, including the U179D code.

10. Do I need a professional mechanic to fix the U179D code?

While some basic troubleshooting can be done at home, a professional mechanic with advanced diagnostic tools may be needed to pinpoint and resolve the issue effectively.