Body, generic

B0235 Brake Lamp Circuit

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

No publicly available J2012 list contains B0235, nor does any carmaker describe it, which leaves it unverified; side-specific brake lamp codes are B0850 and B0851. Stop lamps send a steady red signal rearward while the driver brakes, and FMVSS 108 also demands a third stop lamp mounted high. The brake light switch at the pedal triggers them, directly or via a body module. HELLA describes a Golf V in which one 21 W bulb works as tail lamp on a PWM signal of about 5.7 V and as stop lamp at a full 13.5 V, so one wiring fault can hit both jobs. On a Mitsubishi Grandis, moisture inside the brake light switch even lit the traction and stability warning lamps. A dark brake lamp raises the risk of being hit from behind.

Likely causes

Stop lamp bulb or LED unit failed
Brake light switch misadjusted, worn or wet inside
Blown fuse or broken wire, often in the tailgate or boot lid harness
Corroded lamp holder or plug in the rear light cluster

Symptoms

  • One or more brake lamps stay dark when the pedal is pressed
  • Bulb warning shown, sometimes together with traction or stability warning lamps
  • Safety note: following traffic gets no braking signal; repair before further driving

Repair estimate

DifficultyEasyDIY possible
Parts and labour€10–200
Time0.2–1.5 h

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

Parts involved

brake lampbrake light switchbody wiring harness

Related codes

B0850B0851

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