B101A15 - Crash sensor, driver front airbag, open circuit or short to positive airbag control unit fault

What does error code B101A15 mean in the airbag control unit?

Error code B101A15 reports a problem with the crash sensor of the driver-side front airbag. The fault type behind the base code is an open circuit or a short circuit to positive. The airbag control unit stores the entry and switches on the airbag warning light.

The control unit evaluates the signal from the crash sensor in order to deploy the driver's front airbag in an accident. If the connection to the sensor is interrupted, or if voltage is wrongly present there, the control unit receives no usable signal.

That the sensor fails from the control unit's point of view does not necessarily mean that the sensor itself is faulty. The wiring, the connector or the evaluation in the control unit can also prevent the signal.

This meaning applies to Volkswagen. For Skoda, the code has appeared in the fault memory of the Citigo.

How do you recognise error code B101A15?

The airbag warning light in the instrument cluster stays on permanently. The error code can be read from the fault memory with a diagnostic tool and does not stay gone permanently after being cleared.

• The airbag warning light does not go out after starting.
• The entry appears in the fault memory of the airbag control unit.
• Clearing helps only briefly, and the code is stored again.
• Driving behaviour and the engine stay unchanged, only the airbag protection is limited.

What causes error code B101A15?

Behind it is either a broken wire or a short to positive in the crash sensor circuit. The connector, wiring, sensor or the airbag control unit may be responsible.

• A loose or corroded connector at the sensor or at the control unit.
• A broken or chafed wire.
• A crash sensor that is faulty.
• A fault in the electronics of the control unit, for example due to moisture or aged solder joints.

Voltage spikes caused by a weak battery or by jump-starting can put additional strain on the electronics.

In which vehicles does error code B101A15 occur?

Error code B101A15 is known in the Volkswagen Golf Sportsvan and the Skoda Citigo. The list is not complete, and in other vehicles the code may have a different meaning.

What always counts is the fault memory of your own vehicle. If the same entry appears there, the description on this page applies, even if your model is not named here.

How is error code B101A15 resolved?

The fault memory is read out with a diagnostic tool, then a specialist workshop checks the connector, wiring and crash sensor. If nothing is found there, the airbag control unit is sent in to Airbag24 for repair.

If the connector, wiring and sensor show nothing unusual, the control unit remains as the cause. To send it in, disconnect the battery, remove the control unit and create a repair order online. Airbag24 usually checks, repairs and tests the unit in 3–4 working days.

The repaired control unit comes back with all vehicle data and is ready for use as soon as it is refitted — no coding or programming is required.

Work on the airbag system belongs in expert hands. This applies to removing the control unit just as much as to any check of connectors, wiring and sensors.