Leapmotor B03X airbag control unit repair

What is a Leapmotor B03X airbag control unit?

When you switch on the ignition in the Leapmotor B03X, the airbag control unit first runs a self-test, recognisable by the airbag warning light coming on briefly. As the central control unit of the restraint system (SRS), it evaluates the signals from the crash sensors and decides within milliseconds which airbags and seatbelt pretensioners deploy. If it has registered an accident, it stores crash data and locks itself.

If the light goes out again after the test, the unit has found no fault. If it stays on or comes on while driving, a fault in the system has been detected. The control unit is fitted in the Leapmotor B03X (since 2026).

Its monitoring does not end after start-up: sensors, firing circuits and wiring are checked continuously. If the unit is locked after an accident, the airbag system can no longer deploy in an emergency.

Why is the Leapmotor B03X airbag control unit defective?

Most often the cause is crash data stored in the unit after an accident, even if no airbag deployed. Ageing electronic components, cold solder joints, moisture and corrosion on connectors, or voltage spikes, for example from a weak battery or jump-starting, may also be responsible.

An ordinary diagnostic tool cannot remove this crash data. That is why the lock remains, even if the damage to the vehicle was repaired long ago.

Without an accident, wear and environment play the main role: solder joints tire over the years, contacts oxidise in damp surroundings, and overvoltages in the vehicle electrical system take their toll on the electronics.

How you notice it: the airbag warning light stays on permanently, the fault memory cannot be reset, or the diagnostic tool cannot connect to the control unit.

Common error codes for Leapmotor B03X airbag control unit repair

The codes that occur with the Leapmotor B03X airbag control unit point primarily to communication problems in the vehicle network. Other codes concern internal faults of the unit, firing circuits or stored crash data.

For this model, the following code is known to occur with airbag faults.

• U0151 → Communication with the airbag control unit interrupted

Error codes are read out with a diagnostic tool. A code alone does not necessarily mean the control unit is defective, because connectors, wiring or an airbag module can also be the trigger. Only an inspection shows the actual cause.

What part numbers are available for the Leapmotor B03X airbag control unit repair?

The part number, which defines the exact version of the unit, is on the label on the control unit. Depending on equipment and year of manufacture, the numbers differ within a model series, so enter it in the repair order.

There is no list of known numbers for this model yet. Simply take the number from the label of the removed unit and note it in the repair order.

The route to repair looks like this: first have the fault memory read out, then disconnect the battery and remove the control unit. Then create a repair order online and send in the unit. At Airbag24, checking, repairing and testing usually take 3–4 working days. Whether the unit is really defective only becomes clear from the fault memory read-out or the inspection.

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.