Network, generic

U0481 Invalid Data Received From Automatic Lighting Control Module

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

U0481 means a module still receives frames from the automatic lighting control module but refuses their content, for instance an ambient-light value outside its range, a frozen message counter or a failed checksum; silence from that unit would be U0180. The unit decides from a light sensor, often housed with the rain sensor behind the windscreen, when the headlamps come on. No manufacturer documents U0481 publicly. Mazda shows how such a sensor flags its own trouble: on the 2019 Mazda3 (SA-035/19) heat drives the rain and light sensor beyond its operating range, the auto-light function pauses with B10AD:09 and resumes once the cabin cools. For automatic beam switching FMVSS 108 asks for an indicator telling the driver when the system is in control. Lights must be switched by hand; no MIL.

Likely causes

Light or rain/light sensor delivering values outside its range, e.g. after heat soak or windscreen replacement
Software or configuration of the lighting module not matching the receiving module
Corroded or loose connector on the bus line to the module

Symptoms

  • Automatic headlamp function unavailable, lights must be switched manually
  • Exterior lighting warning or message in the cluster

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€0–450
Time0.3–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

automatic lighting module

Related codes

U0180U0483U0482U0140

References: static.nhtsa.gov, law.cornell.edu, hella.com, en.wikipedia.org.