Quick Answer

U0199 means: U0199 signifies a communication failure between the ECM and BCM in your vehicle.

Fix: Check and replace faulty components Cost: $300 - $800 Time: 90-180 minutes

Can I drive with U0199? Immediate attention is recommended to prevent further electrical issues.

Common Questions

What does U0199 mean and how does it affect my car?

U0199 indicates a communication issue between your vehicle's Engine Control Module and Body Control Module. This can lead to various electrical problems, such as malfunctioning lights, windows, and even starting issues. Immediate attention is crucial to prevent serious electrical failures that could compromise safety.

What are the most common causes of U0199 and how much does it cost to fix?

Common causes include a faulty Body Control Module, damaged wiring, and poor connections. Repair costs range from $100 to $800 depending on the necessary repairs, with BCM replacement being the most expensive option.

Can I drive my car with U0199 or should I stop immediately?

It's advisable to stop driving your vehicle if you experience symptoms like non-functional lights or starting issues. Ignoring U0199 could lead to more severe electrical problems that can compromise safety.

How can I diagnose U0199 myself using GeekOBD APP?

Using the GeekOBD APP, you can perform a quick scan of your vehicle's OBD-II system to retrieve the U0199 code. The app will also provide freeze frame data to help you understand when the issue occurred, allowing you to pinpoint potential causes.

What vehicles are most commonly affected by U0199?

Commonly affected vehicles include the 2015-2018 Chevrolet Equinox, 2016-2019 GMC Terrain, and other GM models within those years. Keep an eye on manufacturer recalls related to BCM issues.

How can I prevent U0199 from happening again?

Regular maintenance checks, including inspecting wiring and connectors, can help prevent U0199. Additionally, ensuring your vehicle's electrical components are kept dry and secure can minimize the risk of BCM failures.

What is U0199?

DTC U0199 indicates that there is a communication breakdown between the Engine Control Module (ECM) and the Body Control Module (BCM). This code is often triggered when the BCM fails to send or receive data correctly from the ECM, which can disrupt various electrical functions in the vehicle. Symptoms can vary widely, including malfunctions in lighting systems, power windows, central locking, and other electronic accessories. In practical terms, this means that your car may exhibit erratic behavior such as lights flickering, windows not operating as expected, or even the engine not starting. The issue may stem from a wiring problem, a faulty BCM, or even an issue with the vehicle's battery or fuses. If left unresolved, a U0199 code can lead to more significant electrical issues, impacting your vehicle's overall reliability and safety.

System: U - Network (Communication, CAN Bus)

Symptoms

Common symptoms when U0199 is present:

  • The check engine light may remain illuminated consistently, indicating a persistent issue.
  • You might experience intermittent or complete failure of power windows, making it difficult to operate them.
  • Central locking system may malfunction, causing doors to lock or unlock erratically.
  • The vehicle’s lighting system may flicker or fail, which can be a safety concern during nighttime driving.
  • Engine may crank but fail to start due to communication issues between modules.

Possible Causes

Most common causes of U0199 (ordered by frequency):

  1. The most common cause is a faulty Body Control Module (BCM), which is likely in over 60% of cases. This can happen due to manufacturing defects or exposure to moisture.
  2. A damaged or corroded wiring harness can cause communication failures, often due to wear and tear or exposure to the elements.
  3. Loose or poor connections at the BCM or ECM can lead to intermittent communication issues. Regular inspection can prevent these problems.
  4. Less common but serious causes include issues with the vehicle's main battery or alternator that can affect module operations.
  5. A rare cause could be software glitches in the BCM or ECM, which may require reprogramming or an update.

U0199 Repair Costs

Cost Breakdown by Repair Type

BCM Replacement

Replacing the faulty Body Control Module with a new or refurbished unit.

  • Total: $300 - $800
  • Success rate: 80%
Wiring Repair

Repairing or replacing damaged wiring or connectors associated with the BCM.

  • Total: $100 - $300
  • Success rate: 90%
Software Update

Updating or reprogramming the BCM or ECM software to resolve communication issues.

  • Total: $50 - $150
  • Success rate: 70%
Money-Saving Tips for U0199
  • Start with the most common and least expensive repairs first
  • Use GeekOBD APP to confirm diagnosis before replacing expensive parts
  • Consider preventive maintenance to avoid future occurrences
  • Compare prices for OEM vs aftermarket parts based on your needs
  • Address the issue promptly to prevent more expensive secondary damage

Diagnostic Steps

Professional U0199 Diagnosis Process

Follow these systematic steps to accurately diagnose U0199. Each step builds on the previous one to ensure accurate diagnosis.

Step 1: Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion (5-10 minutes)

Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion (5-10 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 2: Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context (10-15 minutes)

Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context (10-15 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 3: Step 3: Component testing - Use a multimeter or specific diagnostic tools to test suspected components like the BCM and wiring (20-30 minutes)

Step 3: Component testing - Use a multimeter or specific diagnostic tools to test suspected components like the BCM and wiring (20-30 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 4: Step 4: System function test - Verify proper operation after repairs and clear codes using the GeekOBD APP (10-15 minutes)

Step 4: System function test - Verify proper operation after repairs and clear codes using the GeekOBD APP (10-15 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 5: Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success (15-20 minutes)

Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success (15-20 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.

Important Notes

  • Always verify the repair with GeekOBD APP after completing diagnostic steps
  • Clear codes and test drive to ensure the problem is resolved
  • Address underlying causes to prevent code recurrence

Real Repair Case Studies

Case Study 1: BCM Replacement in a 2017 Chevrolet Equinox

Vehicle: 2017 Chevrolet Equinox, 45,000 miles

Problem: The customer reported that the central locking system was malfunctioning and the check engine light was on.

Diagnosis: After scanning the OBD-II system with GeekOBD APP, we found the U0199 code. A visual inspection revealed corroded wiring connected to the BCM.

Solution: Replaced the BCM and repaired the damaged wiring harness.

Cost: $600 (parts: $400 for BCM, $200 for wiring repair)

Result: Post-repair, the locking system worked perfectly, and the check engine light turned off.

Case Study 2: Software Update for a 2016 GMC Terrain

Vehicle: 2016 GMC Terrain, 50,000 miles

Problem: Customer complained of intermittent electrical issues and the check engine light was illuminated.

Diagnosis: Using the GeekOBD APP, we confirmed the U0199 code and determined that the BCM software needed updating.

Solution: Performed a software update on the BCM to correct communication errors.

Cost: $100 (software update)

Result: The vehicle ran smoothly after the update, with no further electrical issues reported.

Diagnose U0199

Use GeekOBD APP for professional diagnosis!

  • Real-time data monitoring
  • Advanced diagnostic features
  • Step-by-step repair guidance
  • Professional-grade analysis

Code Information

Code: U0199
System: Network (Communication, CAN Bus)
Severity: HIGH
Category: Network Codes