Audi R8 42 Spyder airbag control unit repair

What is an Audi R8 42 Spyder airbag control unit?

In the Audi R8 42 Spyder, the airbag control unit is the central control unit of the restraint system (SRS). It evaluates what the crash sensors report and, in an impact, triggers the appropriate airbags and seatbelt pretensioners within milliseconds. It makes faults in the system visible through the airbag warning light.

The unit is installed in the Audi R8 42 Spyder (2010 to 2015). During operation it continuously monitors itself and everything connected to it: sensors, squib circuits and power supply. If it finds an inconsistency, it stores an entry in the fault memory and switches on the warning light.

After an accident, the control unit records crash data and locks itself. As a driver, you will usually notice this as a light that no longer goes out.

Why is the Audi R8 42 Spyder airbag control unit defective?

The most common cause is crash data stored in the unit after an accident, even if no airbag was triggered. Ageing electronic components, cold solder joints, moisture and corrosion on connectors, or voltage spikes may also be responsible.

A normal diagnostic tool cannot remove stored crash data. That is why the airbag control unit in the Audi R8 42 Spyder keeps showing a fault, even when nothing can be seen on the outside of the vehicle.

Something can also fail without an accident: electronic components age, solder joints turn cold, and moisture together with corrosion attacks the connectors. Voltage spikes can be caused, for example, by a weak battery or by jump-starting.

How you can tell there is a problem: the airbag warning light stays on permanently, the fault memory cannot be reset, or the diagnostic tool cannot establish contact with the control unit.

Common error codes for Audi R8 42 Spyder airbag control unit repair

In the Audi R8 42 Spyder, the codes point to several types of faults, namely internal faults of the control unit, the power supply and the squib circuits of the airbags. They become visible as soon as a diagnostic tool reads the fault memory.

The following entries are known for this vehicle:

• 65535 → General internal fault in the control unit
• 00532 → Supply voltage too low, occurring sporadically
• 00588 → Driver airbag squib circuit, resistance fault
• 00590 → Front passenger airbag squib circuit, fault detected
• 01217 → Front side airbag squib circuit, driver side, resistance fault
• 01218 → Front side airbag squib circuit, front passenger side, resistance fault

The entries are read out with a diagnostic tool. However, a single entry does not prove that the control unit is defective, as connectors, wiring or an airbag module may equally be to blame. Only testing the unit brings clarity.

What part numbers are available for the Audi R8 42 Spyder airbag control unit repair?

The part number, which defines the exact version of the control unit, is on its label. Because equipment and year of manufacture vary within a model series, different numbers occur; it is therefore worth checking the label before you send the unit in.

Known numbers for the Audi R8 42 Spyder are shown in the following overview, which makes no claim to completeness:

• 420959655Z0K

Compare the number on your unit with this overview. This only ensures that it is the right unit. Whether there is a defect only becomes clear by reading out the fault memory or by testing.

The route to repair is quickly described. First, have the fault memory read out. Then disconnect the battery and remove the control unit. Next, create a repair order online, and finally send the unit to us. At Airbag24, testing, repairing and checking 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.