Network, generic

U048B Invalid Data Received From Headlamp Leveling Control Module B

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

U048B concerns the second headlamp leveling control module, B, whose messages reach the receiver but are discarded as corrupt or implausible; if B fell silent, U018A would be logged, while module A has U0482 and U0181. A second address is needed where each headlamp carries its own electronics or a central unit works with lamp-side controllers. No maker assigns the letter publicly or documents U048B. Comparable lamp-side faults appear under brand codes: Mazda's AFS control module on the 2024 CX-90 falsely flagged B10A3:86, an error signal from the left swivel actuator, until new software arrived (09-039-24), and GM had the headlamp control module of the 2016 Buick Cascada set up again to clear B101E and a leveling warning (16-NA-044). Expect a lighting warning; no MIL.

Likely causes

Software of the lamp-side or leveling module misjudging actuator feedback
Setup or configuration of the headlamp module not completed after assembly or replacement
Moisture or poor contact at the connector of the second headlamp

Symptoms

  • Headlamp leveling or adaptive lighting warning
  • Beam height on one side no longer adjusted

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€0–700
Time0.5–2.5 h

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

Parts involved

headlamp leveling module b

Related codes

U018AU0482U0181

References: static.nhtsa.gov, static.nhtsa.gov, hella.com.