12 51 001 Replacing section of wiring harness for engine (N47D20 O1)
IMPORTANT:
Read and comply with notes on protection against electrostatic damage ESD protection).
Necessary preliminary work:
- Read out the fault memory of the DDE control unit.
- Switch off ignition.
- Disconnect BATTERY EARTH LEAD .
- Remove INTAKE FILTER HOUSING .
- Remove INTAKE PORT .
- Remove rear acoustic cover.
- Remove sound insulation on injectors.
- Remove front UNDERBODY PROTECTION .
Release screws (1).
Detach coolant hose from cover of electronics box.
Remove electronics box cover (3).
Unlock all connectors (1) from control unit and disconnect.
Detach rubber grommets (2) from electronics box. Place wiring harnesses to the side.
Installation note:
Make sure grommets are correctly fitted (watertightness).
Pull out fasteners (1) in direction of arrow.
Push back sockets (2) and detach engine wiring harness from connector housing.
Release screw (1).
Release cable channel (2).
| Unlock and disconnect following connectors and lines | Note |
|---|---|
| Unlock connector on hot film air mass meter and disconnect | |
| Unlock connector on exhaust turbocharger and disconnect | |
| Unlock connector on all electric changeover valves on carrier plate and disconnect | |
| Release and unplug connector from exhaust pressure sensor | |
| Unlock connector on exhaust-gas temperature sensor and disconnect | |
| Unlock connector on oxygen sensor and disconnect | |
| Unlock connector on vacuum electric changeover valve (exhaust-gas recirculation) and disconnect | |
| Unlock connector on exhaust-gas recirculation valve and disconnect | |
| Unlock connector on coolant temperature sensor and disconnect | |
| Unlock connector on intake plenum intake adjuster and disconnect | |
| Unlock connector on intake pressure sensor and disconnect | |
| Unlock connector on rail pressure sensor and disconnect | |
| Unlock connector on rail pressure regulating valve and disconnect | If fitted: |
| Unlock connector on camshaft sensor and disconnect | |
| Unlock connector on alternator and disconnect | |
| Unlock connector on air conditioning compressor and disconnect | |
| Unlock connector on intake air temperature sensor and disconnect | |
| Unlock connector on oil pressure sensor and disconnect | |
| Release nut (1) on starter motor, detach cable (terminal 50) | |
| Unlock connector on transmission and disconnect | Automatic only |
| Unlock connector on crankshaft sensor and disconnect | |
| Unlock connector on throttle body and disconnect | |
| Unlock connector on exhaust-gas recirculation temperature sensor and disconnect | |
| Unlock connector on high pressure pump and disconnect | |
| Unlock connector on fuel pressure/temperature sensor and disconnect | |
| Release and unplug connector from preheating control unit |
Release wiring harness from clips and clamps.
Feed out wiring harness and remove.
Installation note:
Check wiring harness installation arrangement.
Check plug connections for correct fit.
Check stored fault message.
Delete fault memory.