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B12BC12 — Left rear side marker lamp bulb, Short circuit to B+
Left rear side marker lamp bulb, Short circuit to B+. The Taycan, 911 (992), Panamera (971), Panamera (972) and Cayenne report this code; below is which control unit sets it on each model and how to read and clear it.
Which models and control units set B12BC12
How to read and clear B12BC12
- Plug a standard ENET (Ethernet-to-OBD) cable into your Porsche's OBD port and your Mac or Windows PC.
- Open STEUER14, pick your car and run a fault scan: every control unit is read, and B12BC12 shows with its status, its full description and the freeze frame when the unit stores one.
- Fix the cause first, then clear the fault memory and scan again to check it stays away. Reading and clearing fault codes is free on every control unit.
More about fault memory in the manual →
Download STEUER14 — free fault readingOther codes of the Comfort System Module
| B122312 | Rear wiper motor – short circuit to B+ |
| B122313 | Rear wiper motor – open circuit |
| B126301 | Filler flap lock motor – electrical fault while unlocking |
| B126511 | Rear window heating relay – short circuit to ground |
| B126515 | Rear window heating relay – short circuit to B+ or open circuit |
| B12BC11 | Left rear side marker lamp bulb, Short circuit to ground |
| B12BC13 | Left rear side marker lamp bulb, Open circuit |
| B12BC15 | Left rear side marker lamp bulb, Open circuit/short circuit to B+ |
| B12BD11 | Right rear side marker lamp bulb, Short circuit to ground |
| B12BD12 | Right rear side marker lamp bulb, Short circuit to B+ |
| B12BD13 | Right rear side marker lamp bulb, Open circuit |
| B12BD15 | Right rear side marker lamp bulb, Open circuit/short circuit to B+ |
All 616 codes of this control unit →
Fault names come from the manufacturer's diagnostic data. STEUER14 is independent and not affiliated with Porsche AG. A code tells you what a control unit detected, not always which part failed — check wiring, supply voltage and related codes before replacing parts. STEUER14 shows each fault's full description, status and freeze frame on the car.