BYD Dolphin Surf 1st generation airbag control unit repair

What is a BYD Dolphin Surf 1st generation airbag control unit?

The airbag control unit in the BYD Dolphin Surf 1st generation is the central unit of the restraint system (SRS). It evaluates what the crash sensors report and, in an accident, decides within milliseconds which airbags and seatbelt pretensioners fire. It signals faults to you through the airbag warning light.

When you switch on the ignition, the airbag warning light comes on briefly and goes out again. Behind this is a self-test that the control unit runs at every start. If the light stays off, it has assessed the squib circuits, sensors and wiring as being in order. It also checks the system continuously while you drive. The control unit is fitted in the BYD Dolphin Surf 1st generation (since 2025).

If there has been an accident, the unit stores crash data and locks itself.

Why is the BYD Dolphin Surf 1st generation airbag control unit defective?

Most often the cause is crash data left behind by an accident, even if no airbag was deployed; a standard diagnostic tool cannot delete it. Ageing electronic components, cold solder joints, moisture with corrosion on connectors and voltage spikes are also possible causes.

A weak battery or a jump start can produce voltage spikes that damage the electronics. If moisture gets in, the contacts on the connectors corrode. Components that have aged over the years and cold solder joints cause intermittent faults until the unit finally fails completely.

How you notice it: the airbag warning light stays on permanently, the fault memory cannot be reset, or the diagnostic tool finds no connection to the control unit. If you come across one of these signs, you should have the unit checked.

Common error codes for BYD Dolphin Surf 1st generation airbag control unit repair

The codes for the BYD Dolphin Surf 1st generation airbag control unit cover various areas: faults in the control unit itself, interruptions in communication over the data bus, a supply voltage that is too low or too high, airbag modules that are not connected and the recording of an impact.

The following error codes occur with this control unit:

• B16AE00 → Fault in the SRS control unit
• B17A000 → Internal control unit fault
• B17A200 → Crash recording in control unit locked
• B17A600 → Frontal impact detected by control unit
• B17A800 → Data bus connection interrupted
• B1694 → Supply voltage too low
• B1695 → Supply voltage too high
• B1600 → Driver airbag not connected correctly

Error codes are read out with a diagnostic tool. The appearance of a code does not yet prove a defect in the control unit, because connectors, wiring or an airbag module can also be the cause. Only the inspection shows what is behind it.

What part numbers are available for the BYD Dolphin Surf 1st generation airbag control unit repair?

You will find the part number on the label of your control unit; it defines its exact version. Depending on equipment and year of manufacture, the numbers differ even within the same model series, so it is worth looking at the label.

The number is part of the repair order: read it from your unit and enter it there. Whether the unit is defective is only shown by reading out the fault memory or by the inspection at our workshop.

The route to repair looks like this: have the fault memory read out, disconnect the battery and remove the control unit. Then create a repair order online and send the unit in. Checking, repairing and testing usually take 3–4 working days at Airbag24.

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.