Airbag control unit with part number 550752100

What does the airbag control unit 550752100 do?

The airbag control unit 550752100 forms the central controller of the restraint system (SRS) in Renault vehicles. It evaluates the signals from the crash sensors and decides in an accident, within milliseconds, which airbags and seatbelt pretensioners are triggered.

During normal driving the unit monitors all connected components continuously. If it detects a fault, it indicates this via the airbag warning light in the instrument cluster.

After an accident the control unit stores crash data and locks itself.

Why does the control unit 550752100 fail?

The most common cause is crash data stored after an accident, even if no airbag was triggered. Other possible causes include aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes, for example from a weak battery or a jump start.

An ordinary diagnostic tool cannot reach the crash data, so it cannot erase them. That makes them the first suspicion in the event of a failure, even if the fault shows up differently.

Which of the other causes applies only becomes apparent during the test on the test bench.

How can you tell that the 550752100 is defective?

Typical signs of a defect in the 550752100 are an airbag warning light in the instrument cluster that lights up permanently or intermittently, as well as fault messages in the display.

• Airbag warning light in the instrument cluster lights up permanently or intermittently
• Error message in the instrument cluster
• Diagnostic tool receives no connection to the control unit
• Fault memory cannot be cleared

With such a defect, airbags and seatbelt pretensioners may not deploy in an emergency. The control unit reports its own condition, so the warning light is not a side issue but the signal you should take seriously.

Which vehicles is the 550752100 fitted in?

The 550752100 is fitted in these vehicles: Renault Master II (1997-2010).

You will find the vehicles this part number belongs to here:

• Renault Master II (1997-2010)

Comparing the part number on the label of the removed unit with this page tells you that it is the right unit. Whether it is actually defective is established only by the fault memory, which you have read out beforehand: it shows whether the control unit itself is the cause or whether a plug or cable is affected.

For the same vehicles, we also repair control units with the part numbers 605045200, 8200098404, 8200381668, 8201001327.

How does the repair of the 550752100 work?

For the repair of the 550752100, have the fault memory read out first and enclose the log; then disconnect the battery and only afterwards remove the control unit. Processing at Airbag24 usually takes 3–4 working days.

This order is mandatory for safety reasons. Afterwards you create a repair order online and pack the unit well before sending it.

Airbag24 checks the unit on the test bench, repairs defective components, erases stored crash data and carries out a function test. After that, your own unit is returned to you.

Our repairs come with 2 years' statutory liability for defects. 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.

How does the control unit 550752100 get to Airbag24?

You send the control unit 550752100 as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 returns it to you by UPS.

Put the printed repair order into the parcel and pack the unit shock-proof.