Removal and Replacement

Special Tool Information:

Testing:
After working on the driver's airbag and belt tensioner restraint system, the system must be tested by means of the pulse display. This test is described at the end of this operation.

Removing:





- Switch ignition (1) off.
- Disconnect and cover battery negative terminal.
- Remove foot mat in passenger's footwell.
- Unscrew 4 clips (2) on foot rest and remove foot rest.
- Disconnect red 10-pin plug connection airbag (X29/9) in front passengers footwell.
- Disconnect control knobs (6) for blower and air distribution switch.
- Unscrew nuts on control unit (6) (width across flats 24 mm)
- Remove ash tray.
- Unscrew 2 phillips screws (4) on ash tray housing and remove housing.
- Press out cover on control unit and remove downwards.
- Pull off electrical connections on back.
- Loosen bolts (7) on retaining plate for control unit
- Push air distribution switch toward the right and push blower switch upwards out of retaining plate.
- Pull retaining plate slightly backwards and unclip temperature selector wheels (10).
- Remove retaining plate.
- Pull off electrical connections and vacuum lines, remove blower switch.
- Pull off plug connection on control unit.
- Remove radio (5).
- Remove lateral right-hand covering grid plate (6) on center console.
- Unscrew torx bolts (11) on control unit.
- Remove control unit.
- Install in reverse order noting the following.

Installation Note: Arrow on control unit must point in driving direction. Install in reverse sequence.

Connection Diagram - Pulse Display/Meter:

013 Pulse meter
G1 Battery
X92 Test coupling for diagnosis, 8-pin (flashing code)

Testing After Renewing the Control Unit:
There is a diagnosis program integrated in the control unit to test the control unit and the electrical components of the airbag system. When a fault is detected, the warning lamp (A1e15) does not go out after 4 s (previously 10 s). The faults detected are stored and may be called up in the form of a pulse display by means of the warning lamp (A1e15) or digitally by means of a pulse meter.

Note on Pulse Display:
The digits 1 - 10 appear on the display of the pulse meter. A 1 signifies that no fault is stored in the system. All other numbers are assigned to a certain group of faults. If there are several faults in the system the fault with the lowest pulse number is displayed first.

- If the light-emitting diode "U-Batt" lights up after connection, the pulse meter and power supply for the pulse meter are in order.
- When the first number reappears during the test after at least two or more pulse outputs (numbers) all faults have been read.

Diagnosis With Pulse Display:
- Connect pulse meter in accordance with the connection diagram.

NOTE: The light-emitting diode "U-Batt" in the display must light up.

- Switch on ignition.
- Press the start button for between 2 and 4 s.
- Display 1 means no fault in the system. If another number appears, rectify the fault in accordance with the fault-finding flow diagram. [1][2]Component Tests and General Diagnostics