93D1 - Overvoltage in the power supply airbag control unit fault

What does error code 93D1 mean in the airbag control unit?

Error code 93D1 indicates, on BMW vehicles, that an overvoltage has been detected in the power supply of the airbag control unit, that is, a voltage above the permitted range. The affected part is therefore the power supply of the airbag control unit itself, because the control unit detects the overvoltage, stores the fault in the fault memory and switches on the airbag warning light.

The airbag control unit is part of the restraint system (SRS), because it triggers the airbags in the event of a crash. As long as the fault is stored, the airbag warning light stays on.

The code therefore describes a state of the power supply that the control unit itself detects.

How do you recognise error code 93D1?

Error code 93D1 shows up as an airbag warning light on the dashboard that stays permanently lit and does not go out on its own. The code is stored in the fault memory and cannot be permanently erased; it is read out with a diagnostic tool connected to the vehicle.

The finding therefore shows on the airbag warning light and in the fault memory at the same time. As long as the entry is there, the fault is not considered resolved.

What causes error code 93D1?

The possible causes are voltage spikes from a weak battery or a jump start, aged electronic components, faulty soldered joints, and moisture or corrosion in the airbag control unit. For this finding, the cause therefore lies in the control unit itself and not only in a plug or a cable.

• voltage spikes from a weak battery or from a jump start
• aged electronic components in the control unit
• faulty soldered joints in the control unit
• moisture or corrosion in the control unit

Which of these causes applies in an individual case only becomes clear once the control unit has been tested.

In which vehicles does error code 93D1 occur?

Error code 93D1 is known on BMW vehicles, for example on the models BMW X3 F97 M, BMW X4 F98 M, BMW X6 F96 M and BMW iX3 NA5. So far, the code is only known for the BMW brand, to which all the model series mentioned belong.

On other vehicles the meaning of this code may differ, and the list is not complete. What matters, therefore, is the specific vehicle on which the code occurs, that is, make, model and model series.

How is error code 93D1 resolved?

Error code 93D1 is resolved by first reading out the fault memory with a diagnostic tool, so that the cause can be narrowed down more precisely. If the cause lies in the control unit itself, the unit is sent in for repair to Airbag24 in Berlin after removal, via a repair order.

Work on the airbag system should be left to qualified specialists.

If the cause lies in the control unit, first disconnect the battery and then remove the control unit. Then create a repair order online and send the unit to Airbag24.

Checking, repairing and testing usually take 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.