Lotus 2004 Eleven Service Notes page 485

Lotus Service Notes
7. Centre vent panel and radio surround: Release the two screws at each side of the panel and withdraw.
8. Fascia top panel: Remove the 5 screws securing the rear edge of the panel to the dash rail, and withdraw
the panel rearwards to disengage the two spigots from the base of the windscreen surround. Disconnect
the speaker cables.
9. SDM: Unplug the harness connector from the SDM. Release the four retaining nuts, and withdraw the
sensor and diagnostic module from its mounting bracket.
Refitment of the SDM is a reversal of the removal procedure, but remember to check that the tether strap
bracket for the airbag trimmed door has been secured before the fascia top panel is fitted, and that new push
fasteners for the airbag door will be required. Use Scan 3 tool or Lotus TechCentre to configure airbag system.
WD.9 - DRIVER AIRBAG MODULE
WARNING: Safety precautions must be observed when handling a deployed airbag. After deploy-
ment, the airbag surface may contain a white packing powder used to ease deployment, together with
a small amount of sodium hydroxide dust, a by-product of the sodium azide reaction during deploy-
ment that can be irritating to the skin if left on for an extended period of time. Always wear gloves and
safety glasses when handling a deployed inflator module, and wash your hands with a mild soap and
water afterwards.
The driver's airbag (or inflator module) is housed in the hub of the steering wheel, beneath a moulded trim
cover designed to hinge open in the event of deployment. The module comprises:
- an inflatable fabric bag;
- an inflator (canister of gas generating material)
- an initiator (or 'squib')
When the vehicle suffers a forward deceleration of sufficient magnitude to close both the safing sensor
and integrated accelerometer within the SDM, current flows through the deployment loop of both the driver and
passenger airbag module initiators and ignites the gas generating material. Each bag inflates in a fraction of a
second, the driver's bag bursting open the steering wheel centre trim cover, and then deflates via vents in the
bag, with the whole cycle taking less than one second. The airbag is designed for a single deployment, and
must then be renewed.
In order to help prevent unwanted deployment of the driver's airbag when servicing the steering column or
other SRS components, a shorting bar is incorporated in the airbag side of the 4-way harness connector plug
located alongside the steering column. The shorting bar operates when the connector is unplugged, to short
across the feed and return connections to the airbag. Thus, if a positive feed, or earth is inadvertently applied
to the connector terminals, both sides of the inflator module will be subject to the same electrical potential, and
no deployment will occur.
To replace driver's airbag
WARNING: The following procedures must be followed in the order listed to temporarily disable the
airbag system whilst working in the immediate vicinity of an airbag. Failure to follow this procedure
could cause unintended airbag deployment, resulting in personal injury and unnecessary airbag system
repairs.
a). Turn off ignition.
b). Disconnect the negative battery cable, and tape back to ensure that it cannot contact the battery terminal.
c). From alongside the steering column, in the area of the column upper fixing, locate and disconnect the
driver's airbag yellow 4-way harness connector plug.
1. Column shrouds: Remove the two screws retaining the top part of the shroud, and the four screws
retaining the lower part, and withdraw both parts from the column.
2. On the reverse side of the steering wheel, locate and remove the two socket head screws, accessible via
holes in the plastic shroud around the steering wheel hub. Withdraw the airbag module and disconnect
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Section WD