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Although, the N54 engine has an all aluminum crankcase, many of the bolts are
still aluminum as on the N52.
This is to reduce any potential confusion between steel and aluminum bolts.
Some bolts, for example, are steel
such as the cylinder head cover bolts. This is possible, due to the plastic
cy
Fig. 17: Identifying Airbag Modules, Airbag Control Unit, Belt Tensioners
Components Location
Safety battery terminal (*)
Side airbag, front seat, left/right (*)
Belt tensioner, front left/right (*)
Airbag unit, passenger side (*)
Airbag module, driver's side (*)
Head airbag, left/right (*)