U054B: Invalid Data from Interior Light Module
The U054B code indicates that the vehicle's network communication module (typically the Body Control Module or BCM) has detected invalid, corrupt, or out-of-range data from the Interior Lighting Control Module (ILCM). This is a network communication code (prefix 'U'), meaning the issue lies in data transmission between modules over the CAN or LIN bus, not necessarily a failure of the lighting components themselves. Per SAE J2012, this code points to a data integrity problem in communication with the module responsible for controlling interior lights, including courtesy, reading, ambient, and vanity mirror lights.
1. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.
2. Most Common Causes
- Faulty Interior Lighting Control Module (ILCM)
- Electrical noise or interference on the CAN/LIN communication bus
- Damaged, corroded, or high-resistance wiring in the communication circuit
- Loose, corroded, or bent pins in the ILCM connector
- Faulty Body Control Module (BCM) receiving the data
- Low battery voltage or charging system fault
- Corrupted or outdated software in the ILCM or BCM
- Incorrect termination resistor on the network bus
3. Symptoms You Will Notice
- Interior lights malfunctioning or not working
- Illuminated check engine or warning light
4. Step-by-Step Diagnosis
Scan for other related codes and check freeze frame data
Inspect ILCM connector for corrosion, damage, or loose pins
Test battery voltage and charging system output
Check CAN/LIN bus wiring for shorts, opens, or high resistance
Verify network termination resistors are correct
Attempt to communicate with ILCM using a scan tool; if no response, suspect module failure
Update ILCM and BCM software to latest version if available
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, it is generally safe to drive with this code, but interior lights may not work properly. Have it diagnosed soon to prevent potential battery drain or further communication issues.
How much does it cost to fix?▼
Diagnosis typically costs $100-$200. Repair costs vary: wiring repairs $100-$300, module replacement $300-$800, software updates $100-$200.