12 90.. Removing and installing/replacing engine control unit box

IMPORTANT: Read and comply with notes on PROTECTION AGAINST ELECTROSTATIC DAMAGE (ESD PROTECTION) .

NOTE: Follow instructions for REMOVING AND INSTALLING CONTROL UNITS .

Necessary preliminary tasks:

Slacken nut (1).

Release screw (2).

Remove heat shield (3).

Fig 1: Identifying Heat Shield, Screw And Nut

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Release screw (1).

Lay filler neck (2) for windscreen washer fluid to one side.

Fig 2: Identifying Windscreen Washer Fluid Filler Neck And Screw

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Release screws (1).

Tightening torque 12 90 2AZ .

Remove electronics box cover (2).

Fig 3: Identifying Electronics Box Cover And Screws

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Unlock all plugs (1) from control unit and detach.

Unclip grommet hold-down device (2) and remove.

Detach rubber grommets (3) from electronics box. Place wiring harnesses to the side.

Installation note:

Make sure grommets are correctly fitted (watertightness).

Fig 4: Identifying Rubber Grommets, Grommet Hold-Down Device And Connectors

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N54 only:

Unlock plug (1) from electronics box fan and pull off.

Fig 5: Identifying Windscreen Washer Fluid Filler Neck And Screw

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Release screws (1).

Tightening torque 12 90 1AZ .

Pull off air duct (2) from the electronics box.

Feed electronics box (3) out upward and remove.

Installation note:

When replacing electronics box, modify DME CONTROL UNIT .

Fig 6: Pulling Off Air Duct From Electronics Box

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Installation note:

When installing the electronics box, insert guide (1) on engine support.

Fig 7: Identifying Engine Support Guide

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