Airbag control unit with part number EM2E-3658100

What does the airbag control unit EM2E-3658100 do?

The airbag control unit EM2E-3658100 is the central control unit of the restraint system (SRS) for BYD. It evaluates the signals from the crash sensors, decides within milliseconds in the event of an accident whether to trigger the airbags and seatbelt pretensioners, and monitors the system continuously. After an accident, it stores crash data and locks itself.

The unit reports faults in the system via the airbag warning light in the instrument cluster. In normal operation it remains inconspicuous and works in the background.

If the control unit fails, the restraint system may not work as intended in an emergency. That is exactly why this component is so important for vehicle safety.

Why does the control unit EM2E-3658100 fail?

The most common cause with the EM2E-3658100 is crash data stored after an accident, even if no airbag has deployed; a normal diagnostic tool cannot erase it. Other causes include ageing electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes, for example from a weak battery or jump-starting.

The crash data is held in the memory of the control unit itself. Its presence does not automatically mean that an airbag has deployed.

A fault can equally lie in the plug or the wiring rather than in the unit. The fault memory read-out shows which case applies.

How can you tell that the EM2E-3658100 is defective?

A defect in the EM2E-3658100 shows up through the airbag warning light in the instrument cluster, which may light up permanently or intermittently. In addition there are fault messages in the instrument cluster, no contact with the diagnostic tool, and a fault memory that cannot be cleared.

• The airbag warning light is on permanently or intermittently.
• A fault message appears in the instrument cluster.
• The diagnostic tool gets no connection to the control unit.
• The fault memory cannot be cleared.

In an emergency, the airbags and seatbelt pretensioners may then fail to deploy. The warning light is therefore a clear reason to have the system checked.

Which vehicles is the EM2E-3658100 fitted in?

The EM2E-3658100 is fitted in these vehicles: BYD Dolphin 1st generation (from 2023). The details come from the assignment of this part number to the models.

This assignment covers the following vehicles:

• BYD Dolphin 1st generation (from 2023)

Compare the part number on the label of the removed unit with this page. That only ensures that you have the right unit. Before removal, have the fault memory read out, because only this log shows whether the control unit is defective or whether a plug or cable is the cause.

How does the repair of the EM2E-3658100 work?

Airbag24 usually processes the EM2E-3658100 within 3–4 working days. The sequence on your side is fixed: first read out the fault memory and enclose the log, then disconnect the battery and only then remove the unit.

Next, create a repair order online and pack the unit well before you send it in. Airbag24 checks it on the test bench, repairs defective components, erases stored crash data and carries out a function test.

The unit then goes 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 EM2E-3658100 get to Airbag24?

The unit either goes to Airbag24 as a parcel or through a UPS collection booked for an extra charge. The EM2E-3658100 comes back to you by UPS after the repair.

Enclose the printed repair order and pack the control unit shock-resistant.