Safety Circuit Breaker: Service and Repair

Battery Interrupt Igniter (N253)

Special tools, testers and auxiliary items required

• Vehicle Diagnostic Tester

Removing

• Follow all safety precautions when working on pyrotechnic components.

• Follow all regulations when disposing of pyrotechnic components. Refer to => [ Airbag, Belt Tensioner and Battery Cut-Out Units, Storing, Transporting and Disposing ] Service Precautions.

• If the airbag indicator lamp (K75) illuminates after a collision, check for stored collision data using the using the Vehicle Diagnostic Tester. If data is present, check if the fault "Resistance Too High" is stored in the DTC memory for the battery interrupt igniter (N253). If it is, replace the battery interrupt igniter (N253).

• The battery interrupt igniter (N253) interrupts the circuit when an airbag deploys. Always replace the battery interrupt igniter (N253) after an airbag deploys.

• The battery interrupt igniter (N253) is available as a replacement part only together with fuse panel A (SA).

• When just replacing the battery interrupt igniter (N253) , remove it from the replacement part and install it in fuse panel A (SA) as follows.

- Turn on the ignition.

- Disconnect the battery ground cable from the battery with the ignition on.

- Remove the vehicle tool kit mount.






- Remove nuts - 2 - and - 3 -.

- Unlock the retaining spring - 3 -.






- Lift the lid - 2 - over the fuse panel A (SA) - arrow - and at the same time remove the battery interrupt igniter.

• Ignore - 1 - in this figure.








Before handling pyrotechnical components (for example, disconnecting the connector), the person handling them must discharge static electricity. For example, by briefly touching the door striker pin.

- Remove the battery interrupt igniter - 4 -.

- Disconnect the electrical connector - 1 - by releasing the locking mechanism - 5 - - arrow -.

Installing

• Follow all safety precautions when working on pyrotechnic components.

• Before handling pyrotechnical components (for example, disconnecting the connector), the person handling them must discharge static electricity. For example, by briefly touching the door striker pin.

Install in reverse order of removal. Note the following:

• Make sure the connectors are installed all the way in and are secure.

Connect the battery with the ignition switched on. Pyrotechnic components could deploy after connecting the battery if they were not repaired correctly. Individuals must not be inside the vehicle when connecting the battery.

- Connect the battery ground cable with the ignition turned on.

- Check the airbag control module DTC memory (J234) and correct any faults, if necessary using the Vehicle Diagnostic Tester.

Tightening specifications, refer to => [ Battery Interrupt Igniter (N253) Overview ] Battery Interrupt Igniter (N253) Overview.