Airbag control unit with part number 98820-1MM1A

What does the airbag control unit 98820-1MM1A do?

The control unit 98820-1MM1A belongs to the restraint system (SRS) of Infiniti. Its task is to check the sensor data and, in a crash, determine which airbags and seatbelt pretensioners should fire. The decision is made within milliseconds. If the system reports a fault, the airbag warning light in the instrument cluster lights up.

Besides evaluating the sensors, the unit continuously monitors the wiring of the airbag components. In this way it detects interruptions or short circuits before they become important in an emergency.

If an accident is registered, the unit stores crash data and locks itself. The lock ends only with the repair.

Why does the control unit 98820-1MM1A fail?

The most common cause is crash data stored in the control unit 98820-1MM1A, even if no airbag has deployed; a normal diagnostic tool cannot erase it. Further causes are ageing electronic components, cold solder joints, moisture and corrosion, and voltage spikes.

The entry is also stored when no airbag fires in the accident.

• ageing components of the electronics
• poorly soldered points
• moisture and corrosion at plug connections
• voltage spikes, for example from a weak battery

During the repair, Airbag24 removes the crash data.

How can you tell that the 98820-1MM1A is defective?

A defect in the control unit 98820-1MM1A shows up as the airbag warning light in the instrument cluster, which lights up constantly or intermittently. Added to this are a fault message, a diagnostic tool without a connection to the control unit, and a fault memory that cannot be cleared.

In that case, airbags and seatbelt pretensioners may fail to trigger in an emergency. This is no minor matter that can be put off.

Therefore have the fault memory read out promptly, so that the cause can be narrowed down.

Which vehicles is the 98820-1MM1A fitted in?

The control unit 98820-1MM1A is fitted in these vehicles: Infiniti M37 Y51 (2010-2013).

Below you see the vehicles for which this part number is intended.

• Infiniti M37 Y51 (2010-2013)

You can compare the part number on the label of the removed unit with this page; this only confirms that it is the correct unit. Whether the unit is defective is shown only by reading out the fault memory, because a cable or a plug can also be the cause.

For the same vehicles, we also repair control units with the part numbers 98820-1MA1C.

How does the repair of the 98820-1MM1A work?

First have the fault memory read out and enclose the log, then disconnect the battery and only then remove the control unit 98820-1MM1A. Next, create the repair order online and send the well-packed unit in. At Airbag24, processing usually takes 3–4 working days.

Airbag24 checks the unit on the test bench, replaces defective components, erases the crash data and carries out a function test. Afterwards you receive your own unit back.

This time applies only to checking, repairing and testing.

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 98820-1MM1A get to Airbag24?

You send the control unit 98820-1MM1A to Airbag24 as a parcel, or book a UPS collection for an extra charge. After the repair, Airbag24 returns it by UPS.

The printed repair order goes into the parcel, and you pack the unit shockproof.