12 51 001 Removing and installing/replacing wiring harness section for the transmission module (S55): Notes

Special tools required: 

• 23 4 050
• 00 2 030

Necessary preliminary work: 

• Read out the fault memory of the DME control unit.
• Switch off ignition.
• Disconnect NEGATIVE BATTERY CABLE .
• Remove CORROSION PROTECTION COVER .
• Remove INTAKE PLENUM .
• Remove front UNDERBODY PROTECTION .
• Remove rear UNDERBODY PROTECTION

Removal: 

Unlock connector (1) and pull off.

Unlock connector (2) and remove.

Detach the wiring harness from the holder (3).

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Unlock connector (1) and pull off from air conditioning compressor.

Unlock connector (2) and pull off from the wiring harness section for sensor system 1.

Unlock connector (3) and pull off from the wiring harness section for sensor system 1.

Release screw (4) and remove ground cable.

Remove connector (5) from DME control unit.

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Lowering transmission: 

Support transmission with special tools 23 4 050, 00 2 030.

Secure transmission to mounting with tensioning strap (1).

Tasks are described in GEARBOX HOLDER .

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Release screws (1).

Slightly lower the transmission.

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Release clamp (1).

Unlock connector (2) and pull off from transmission.

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Release wiring harness if necessary from existing clips and clamps.

Feed out wiring harness and remove.

Installation: 

Secure wiring harness with clamp (1).

Connect and lock the connector (2) on transmission.

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Lift transmission.

Insert screws (1) and tighten.

Tightening torque: 22 32 3AZ .

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Remove the transmission jack.

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Attach connector (1) on the air conditioning compressor and lock audibly.

Attach connector (2) on the wiring harness section sensor system 1 and lock audibly.

Attach connector (3) on the wiring harness section sensor system 1 and lock audibly.

Mount ground cable and tighten screw (4).

Tightening torque: 12 90 3AZ .

Route the connector (5) to the DME control unit.

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Connect and audibly lock the connector (1).

Connect and audibly lock the connector (2).

Attach wiring harness on holder (3).

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Installation note: 

Check wiring harness installation arrangement.

Check plug connections for correct fit.

Check stored fault messages.

Delete the fault memory.

Required follow-up work 

• Install INTAKE PLENUM .
• Install the CORROSION PROTECTION COVER .
• Install front UNDERBODY PROTECTION .
• Installing UNDERBODY PROTECTION at rear
• Connect NEGATIVE BATTERY CABLE .