12 31 020 Removing and installing or replacing alternator (N14, N16, N18)

Necessary preliminary work:

N14 and N18 only:

Release screw.

Remove holder (1) and place to one side.

Fig 1: Identifying Holder And Screw

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Use the spanner (2) to bring the belt tensioner (1) into the working position and hold.

Secure installation position of belt tensioner (1) by sliding locating pin (3) in direction of arrow.

WARNING: Danger of injury!
Remove spanner (2) again from the belt tensioner (1).

Fig 2: Securing Installation Position Of Belt Tensioner By Sliding Locating Pin

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Remove drive belt (4) from alternator.

Release connector and remove.

Release nut (1) and remove positive battery cable.

Tightening torque 12 31 2AZ .

Loosen screws (2) and remove the belt tensioner (3).

Tightening torque: 20 Nm.

Fig 3: Identifying Belt Tensioner Nut, Screws And Plug Connection

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Loosen the screw with a joint extension (1).

Tightening torque 12 31 1AZ .

IMPORTANT: Do not bend refrigerant line.
Bending the line can cause watertightness!

Remove alternator.

Fig 4: Identifying Joint Extension

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