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B120101 — Instrument panel and switch illumination dimmer switch, Electrical error

Instrument panel and switch illumination dimmer switch, Electrical error. 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 B120101

Porsche Taycan

Porsche 911 (992)

Porsche Panamera (971, 2017–2023)

Porsche Panamera (972, 2024–)

Porsche Cayenne (9YA)

How to read and clear B120101

  1. Plug a standard ENET (Ethernet-to-OBD) cable into your Porsche's OBD port and your Mac or Windows PC.
  2. Open STEUER14, pick your car and run a fault scan: every control unit is read, and B120101 shows with its status, its full description and the freeze frame when the unit stores one.
  3. 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 reading

Other codes of the Central Electrics

B11E715Hazard warning lights indicator light – short circuit to B+ or open circuit
B11E811Left front turn signal bulb, Short circuit to ground
B11E815Left front turn signal bulb, Open circuit/short circuit to B+
B11EA11Right front turn signal bulb, Short circuit to ground
B11EA15Right front turn signal bulb, Open circuit/short circuit to B+
B120012Interior light delay (dimmer), Short circuit to B+
B121711Left low beam headlamp bulb, Short circuit to ground
B121715Left low beam headlamp bulb, Open circuit/short circuit to B+
B121811Right low beam headlamp bulb, Short circuit to ground
B121815Right low beam headlamp bulb, Open circuit/short circuit to B+
B121911Left high beam headlamp bulb, Short circuit to ground
B121915Left high beam headlamp bulb, Open circuit/short circuit to B+

All 1472 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.