U054B code meaning
Invalid Data Received From Interior Lighting Control Module A
What U054B means
Interior lighting control module A runs cabin illumination such as dome, footwell and ambient light strips, in newer cars often RGB LED nodes on a LIN line below the body controller. Microchip's reference ambient lighting module shows the data involved: the master sends a command frame with zone, color shares and intensity and asks for a status frame in return, each protected by a LIN checksum at 10.4 kbit/s. When status content from module A arrives but is implausible or corrupted, the receiver stores U054B; if the module stays silent, U024A applies, and module B has U05C0. No manufacturer documents U054B. Courtesy lights may then stay off, color or brightness may change unexpectedly, or entry lighting may fail.
U054B at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U054B
- Interior or ambient lights stay off or flicker
- Ambient color or brightness differs from the setting
Common causes of U054B
- PossibleLED driver node or lighting module internally faulty
- PossibleChafed LIN line or loose connector in trim or headliner
- Less likelyWrong vehicle configuration for the lighting variant
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Interior lighting module a
What each part of U054B means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 4B | The exact fault in that area. |
What to do next
- Note U054B and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U054B
What does U054B mean?
U054B means "Invalid Data Received From Interior Lighting Control Module A". Interior lighting control module A runs cabin illumination such as dome, footwell and ambient light strips, in newer cars often RGB LED nodes on a LIN line below the body controller. It is a generic code, so it means the same on every make.
Is it safe to drive with U054B?
U054B does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U054B fail an emissions test?
U054B is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is U054B to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will U054B clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.