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.
Electrical Feed Pump.
The electric feed pump is located on the clutch unit and is supplied with voltage from the Differential electronic module (DEM).
The pump starts at ignition on and then works up a max. oil pressure of 35 bar. This is to always enable request for full torque. Then the pump is shut off until the pressure has dropped to 50%, then it starts again. If the pump does not reach max. pressure within 15 seconds, it is shut off and is then started again. This is calculated via a current measuring algorithm in the Differential electronic module (DEM). The pump works in intervals so that it is not damaged in case of a malfunction, e. g., leakage, in the system. The time interval that the pump works between depends on the temperature. At normal room temperature the pump runs at approx. 20-30 second intervals.
Four-wheel drive does not function in the event of a fault in the feed pump.
The feed pump can be diagnosed.
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.