Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
12 51 001 Replacing wiring harness section for engine (M57T2)
2012 BMW X5 50iSECTION 12 51 001 Replacing wiring harness section for engine (M57T2)
IMPORTANT:
Read and comply with notes on PROTECTION AGAINST ELECTROSTATIC DAMAGE (ESD PROTECTION)
.
Necessary preliminary tasks:
- Read out fault memory of DME control unit
- Switch off ignition
- Follow INSTRUCTIONS FOR DISCONNECTING AND CONNECTING BATTERY
Disconnect battery negative lead from battery and lay to one side
- Disconnect control unit, refer to REPLACING CONTROL UNIT
- Remove intake air manifold
- Remove UNDERBODY PROTECTION
Unlock tab (1), pull contact carrier (2) in direction of arrow out of housing.
Release screws on cable duct (1).
| Work step | Note: |
|---|---|
| Unlock plug on lambda oxygen sensor and disconnect | |
| Unlock plug on diesel particulate filter temperature sensor and disconnect | |
| Unlock plug on exhaust system pressure sensor and disconnect | |
| Unlock plug on A/C compressor and disconnect | |
| Release nut and disconnect control line from starter motor | |
| Unlock plug on crankshaft sensor and disconnect | |
| Unlock plug on coolant temperature sensor and disconnect | |
| Unlock plugs of all glow plugs and disconnect | |
| Unlock plug on camshaft sensor and disconnect | |
| Unlock plug on air mass sensor and disconnect | |
| Unlock plug on injection system pressure control valve and disconnect | |
| Unlock plug on injection system pressure sensor and disconnect | |
| Unlock plug on fuel metering unit and disconnect | |
| Unlock plug on fuel temperature sensor and disconnect | |
| Unlock plug on oil pressure sensor and disconnect | |
| Unlock plug on electric switchover valve and disconnect | |
| Unlock plug on turbocharger and disconnect | |
| Unlock plug on oil condition sensor and disconnect | |
| Unlock plug on diesel particulate filter temperature sensor and disconnect | |
| Unlock plug on reversing light switch and disconnect | Manual transmissions only |
| Unlock plug on automatic transmission and disconnect | If necessary, remove exhaust system intermediate pipe |
| Unlock plug on preheating control unit and disconnect | |
| Unlock plug on alternator and disconnect | |
| Remove wiring harness Installation: Pay attention to installation position and attachment points |
NOTE:
Now clear the fault memory.
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.