Removing and installing battery isolation igniter N253 — AUDI

🧭 Before you start

Disconnect the battery earth with the ignition on, remove the lower A-pillar trim, fold back the carpet and open the cover. Remove the nuts and positive wire, discharge static, take the igniter out and release its connector. Fit the connector until it clicks, refit the wire and cover, reconnect the battery with the ignition on and nobody inside, then read the airbag event memory and rectify faults.

Fits: platform code 42

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• Observe safety and disposal rules for pyrotechnic components; N253 is one.
• Touch the door striker plate to discharge static before handling the connector.
• Make sure the connector is fully home and engages audibly.
• Reconnect the battery with the ignition on and no one in the vehicle.
• Read the airbag control unit event memory afterwards and rectify any faults.

Written for this job from the workshop steps below · TorqFix editorial.

📋 Procedure

1. ⚠ Observe safety regulations for pyrotechnic components .Observe disposal regulations for pyrotechnic components . — With ignition switched on, disconnect battery earth wire Electrical system27.
2. Remove right A-pillar trim (bottom) .
3. Fold back footwell floor covering in area of A-pillar (passenger side).
4. Turn fasteners (1) and (3) by 90° (anti-clockwise) and open cover (2).
5. Unscrew nuts (2) and (4).

6. Detach the positive wire (5).
7. ⚠ Before handling pyrotechnic components (e.g. unplugging the electrical connector) the mechanic must discharge any static electricity. This can be done by briefly touching the door striker plate, or similar. — Take out the battery isolation igniter (1).
8. Unplug electrical connector (3).
9. To do so, use a small screwdriver (1) to release connector locking element (3) and detach electrical connector (2) from battery isolation igniter N253.
10. ⚠ Observe safety regulations for pyrotechnic components .Before handling pyrotechnic components (e.g. plugging in the electrical connector) the mechanic must discharge any static electricity. This can be done by briefly touching the door striker plate, or similar.Make sure electrical connectors are fitted correctly (as far as stop) and engage audibly. — Switch on ignition.
11. ⚠ The battery must be connected with the ignition switched on. If pyrotechnic components (e.g. airbag or belt tensioner) are inexpertly repaired, this may result in unwanted triggering after connecting the battery. There must not be anyone in the vehicle while you are connecting the battery. — With ignition switched on, connect battery earth wire Electrical system27.
12. Finally read out event memory for airbag control unit using and rectify faults as necessary.

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