Body, generic

B0231 Front Marker Lamp Circuit

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

B0231 is found neither in any publicly available J2012 list nor in public service documents of a carmaker, so the code cannot be verified. The title points to the front marker or position lamps. FMVSS 108 places side marker lamps close to the leading and trailing ends of the body so that, seen from the side, they reveal how long the vehicle is. HELLA lists front marker lights as white, or amber where the headlamps are amber, and mandatory on vehicles wider than 1600 mm. They normally light in the park position of the light switch. A module that switches them electronically can spot a missing load: Ford's patent US4667187A briefly toggles each lamp for about 300 µs and flags a fault when no current change follows. Expect a dark marker lamp and, where fitted, a bulb warning.

Likely causes

Bulb or LED module of the marker lamp failed
Corroded bulb holder or plug in the headlamp area, where spray water reaches it
Feed or ground wire to the front lamp open or shorted

Symptoms

  • One front marker or position lamp stays dark with parking lights on
  • Bulb failure warning in the instrument cluster, where the car has one

Repair estimate

DifficultyEasyDIY possible
Parts and labour€10–120
Time0.2–1 h

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

Parts involved

marker lampbody wiring harness

Related codes

B0239B0830

References: law.cornell.edu, hella.com, patents.google.com.