Airbag control unit with part number 46857578

What does the airbag control unit 46857578 do?

The airbag control unit 46857578 forms the central control of the restraint system (SRS) for Fiat and Opel. It reads out the crash sensors, selects in an accident within milliseconds the airbags and seatbelt pretensioners for triggering, and monitors the system without interruption.

It indicates faults via the airbag warning light in the instrument cluster. After an accident the unit stores crash data and locks itself.

The evaluation runs in fractions of a second. The control unit works closely with the sensors and the firing circuits.

Why does the control unit 46857578 fail?

The most common cause at 46857578 is the storage of crash data after an accident, even without a triggered airbag. A normal diagnostic tool cannot erase this data. Further causes are aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

Airbag24 takes over the erasure of the crash data as part of the repair.

Aged components and cold solder joints lead to faults over time. Moisture and corrosion at plug connections worsen the contact, and voltage spikes, for example from a weak battery or a jump start, put strain on the electronics.

How can you tell that the 46857578 is defective?

A defect on the 46857578 shows up at the airbag warning light in the instrument cluster and at an error message in the instrument cluster. A disturbed connection to the diagnostic tool and a fault memory that cannot be cleared also give clues. In an emergency, airbags and seatbelt pretensioners may then possibly not trigger.

The signs at a glance:

• The airbag warning light lights up permanently or intermittently.
• The instrument cluster shows an error message.
• The diagnostic tool gets no connection to the control unit.
• The fault memory cannot be cleared.

If you notice these signs, have the fault checked promptly.

Which vehicles is the 46857578 fitted in?

The control unit 46857578 is fitted in these vehicles: Fiat Ducato 250 2nd Facelift (2014-2024), 250 (2006-2011), 250 3rd Facelift (from 2023) and 250 1st Facelift (2011-2014); Opel Movano C (from 2021).

The vehicle assignment follows in a list:

• Fiat Ducato 250 2nd Facelift (2014-2024)
• Fiat Ducato 250 (2006-2011)
• Opel Movano C (from 2021)
• Fiat Ducato 250 3rd Facelift (from 2023)
• Fiat Ducato 250 1st Facelift (2011-2014)

Match the part number on the label of the removed unit against this page; that only confirms you have the right unit. Have the fault memory read out beforehand, because only this finding shows whether the control unit is defective or whether the cause lies in a plug or cable.

For the same vehicles, we also repair control units with the part numbers 00046858203, 00046858205, 00046859296, 00046859297, 00046863930, 01356790080.

How does the repair of the 46857578 work?

First have the fault memory read out and attach the log. Then disconnect the battery and only then remove the control unit 46857578. Next create a repair order online and send the unit in well packed.

At Airbag24 the unit is examined on the test bench, defective components are replaced, crash data is erased and a function test is carried out.

Processing at Airbag24 usually takes 3–4 working days. Afterwards your own unit comes back 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 46857578 get to Airbag24?

You send the control unit 46857578 to us as a parcel or book a UPS collection for an extra charge. After the repair Airbag24 sends the unit back to you by UPS.

The printed repair order belongs in the parcel, and the unit must be packed shockproof.