Safety Circuit Breaker: Service and Repair

Battery Interrupt Igniter N253

Special tools, testers and auxiliary items required

• Vehicle Diagnosis Tester

Removing

• Follow all safety precautions when working on pyrotechnic components. Refer to => [ Restraint System Components ] Description and Operation.

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

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

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

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

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

- Turn the ignition on.

- Disconnect the battery Ground (GND) cable with the ignition turned 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 - arrow - and at the same time remove the battery interrupt igniter.

• Ignore - 1 -.








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 -.

- To do this, release the connector lock - 5 - and disconnect the connector - 1 -.

Installing

• Follow all safety precautions when working on pyrotechnic components. Refer to => [ Restraint System Components ] Description and Operation.

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

Installation is reverse of removal, but 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 GND cable with the ignition turned on.

- Check the airbag control module Diagnostic Trouble Code (DTC) memory and correct any faults if necessary. Refer to Vehicle diagnostic tester.

For the correct tightening specifications, refer to => [ Battery Interrupt Igniter N253 Assembly Overview ] Battery Interrupt Igniter.