12 31 020 Removing and installing or replacing alternator (B48)

Necessary preliminary tasks: 

• Disconnect the BATTERY NEGATIVE LEAD .
• Remove the THROTTLE VALVE ASSEMBLY .
• Remove the DRIVE BELT FOR ALTERNATOR .

In so doing:

• Do not  draw off air conditioning refrigerant.
• Do not  detach refrigerant lines from A/C compressor.
• Do not  remove air conditioning compressor; instead, release from bracket only and place to one side.

Removal: 

Slacken nut (1).

Feed out positive battery cable (2) and place to one side.

Unlock and disconnect plugs (3).

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Release screw (1).

Loosen the alternator (2).

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Remove the alternator (1) towards the front in the direction of the arrow.

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Remove the alternator (1) towards the top in the direction of the arrow.

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Preparation for installation: 

Loosen the screws along the arrows.

Remove the tensioning device for the drive belt (1).

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Insert and install the tensioning device for the drive belt (1) on the new alternator.

Tighten the screws along the arrows.

Tightening torque, refer to: 12 31 2AZ .

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Press back the threaded support sleeve (2) in the direction of the arrow to facilitate installing the alternator.

Screw in screw (1) into the threaded support sleeve (2). Turn back the threaded support sleeve (2) in the direction of the arrow using the screw (1).

Unscrew the screw (1) from the threaded support sleeve (2) again.

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Installation: 

Insert the alternator (1) in the direction of the arrow.

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Insert the alternator (1) in the direction of the arrow.

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Install alternator (2).

Tighten down screws (1).

Tightening torque, refer to: 12 31 1AZ .

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Connect the positive battery cable (2) to the alternator.

Tighten nut (1).

Tightening torque, refer to: 12 42 1AZ .

Attach connector (3).

Connector (3) must engage audibly.

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Required reworking: 

• Install the AIR CONDITIONING COMPRESSOR .
• Install the DRIVE BELT FOR ALTERNATOR .
• Install the THROTTLE BODY .
• Connect the BATTERY EARTH LEAD .