Volkswagen LT 2D airbag control unit repair

What is a Volkswagen LT 2D airbag control unit?

In the Volkswagen LT 2D, the airbag control unit is the central control unit of the restraint system (SRS). It continually evaluates the signals from the crash sensors and, in an accident, decides within milliseconds which airbags and seatbelt pretensioners are triggered.

This unit is fitted in the Volkswagen LT 2D (1996 to 2006) and comes from Bosch. While driving, it also monitors itself and the rest of the restraint system, so that a detected fault is shown immediately by the airbag warning light.

If the vehicle has been involved in an accident, the control unit stores crash data and locks itself.

Why is the Volkswagen LT 2D airbag control unit defective?

Most often the cause is crash data stored after an accident, even if no airbag was triggered; an ordinary diagnostic tool cannot erase it. Other possible causes are aged components, cold solder joints, moisture and corrosion on the connectors, and voltage spikes.

A single detected impact is enough to create such an entry, and the unit holds on to it. You cannot remove it with your own diagnostic tool.

Regardless of any accident, the electronics change over the years: solder joints lose contact, and moisture that gets in attacks the connectors. A weak battery or a jump start can cause voltage spikes that damage sensitive circuits in the unit.

A constantly lit airbag warning light, a fault memory that cannot be cleared and a diagnostic tool that cannot connect to the control unit all point to a defect.

Common error codes for Volkswagen LT 2D airbag control unit repair

The codes that occur on this vehicle relate to internal control unit faults, the supply voltage, the squib circuits of the airbags and stored crash data. They show in which part of the restraint system the fault is to be looked for.

Listed below are the codes known for this vehicle, each with its meaning.

• 65535 → Internal memory error in the control unit
• B2013 → Data record missing in the replacement control unit
• 00595 → Crash data stored, impact detected
• 01226 → Crash data stored, driver airbag
• 00532 → Supply voltage outside the permitted range
• 00588 → Driver airbag firing circuit: resistance out of range or short circuit
• 00589 → Passenger airbag firing circuit: resistance too high
• 01217 → Driver-side side airbag firing circuit: circuit fault

The codes are read from the fault memory with a diagnostic tool. A single code does not yet prove, however, that the control unit itself is defective, as plugs, wiring or an airbag module can equally cause the fault. A check provides clarity.

What part numbers are available for the Volkswagen LT 2D airbag control unit repair?

You will find the part number on the label of your control unit, and it determines the exact version. Within one model series there are different numbers depending on equipment and year of manufacture.

The list below contains known numbers for the Volkswagen LT 2D, without claiming to be complete.

• 2D0909601A (Bosch)
• 2D0909601B (Bosch)

Compare the number on your unit with this list. This only tells you whether it is the matching unit; whether it is actually defective only becomes clear from reading the fault memory or from the check.

For the repair, proceed as follows: 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 at Airbag24 usually take 3–4 working days, plus shipping.

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.