12 63 520 Replacing main relay (M62, M54)

Switch off ignition.

Connect DIS Tester.

Detach sealing strips (1).

Fig 1: Detaching Sealing Strips

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Turn tommy bar through approx. 90°.

Remove cover.

Fig 2: Removing Cover

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Release lock (1).

Remove air funnel (2) towards top.

Fig 3: Removing Air Funnel

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Release screws.

Remove cover (1) on control unit box.

Fig 4: Removing Control Unit Box Cover

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Installation: 

Insert fixtures (1) of cover for control unit box in openings (2).

Fig 5: Inserting Fixtures Of Cover For Control Unit Box In Openings

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Order: 

1. Main relay of Digital Motor Electronics.
2. Engine fuses of Digital Motor Electronics.
   Fig 6: Identifying Digital Motor Electronics Main Relay And Engine Fuses

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Notes On Troubleshooting: 

If the starter motor cranks the engine during the starting sequence but the engine fails to fire, then:

1. Check engine fuses.
2. If fuses are blown, replace them completely with fuse holder.
3. Find out why fuses have blown.

   Continue troubleshooting as per DIS instructions.