12 51 210 Replacing wiring harness section for ignition and injectors (N20, N26)

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

Necessary preliminary work:

Read out the fault memory of the DME control unit.
Switch off ignition.
Remove acoustic cover. See REMOVING ACOUSTIC COVER (N20) or REMOVING ACOUSTIC COVER (N26) .
N20 only:
Remove PRESSURE CONVERTER FOR EXHAUST TURBOCHARGER .

Fig 1: Overview Of Wiring Harness Section For Ignition And Injectors

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Overview of wiring harness section for ignition and injectors.

Unlock and remove connector (1) from control unit.

Fig 2: Identifying Control Unit Connector

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Release wiring harness from clamps (1).

Fig 3: Identifying Wiring Harness Clamps

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NOTE: This procedure is applicable to all cylinders.

Unlock and disconnect connectors (1) at injectors.

Slacken nut (2) and remove ground cable (3).

Tightening torque 12 52 2AZ .

Fig 4: Identifying Connectors, Nut, And Ground Cable

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NOTE: This procedure is applicable to all cylinders.
Release connector catch (1) at ignition coil (2) and pull off connector.

Fig 5: Pulling Out Ignition Coil

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Unlock retaining lug (1) in direction of arrow.

Pull cable channel (2) from cylinder head cover.

Pull out and remove wiring harness section for injectors and ignition coils.

Fig 6: Pulling Cable Channel From Cylinder Head Cover

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NOTE: Check stored fault messages.
Clear diagnostic fault entries from fault memory.