Audi Workshop Service and Repair Manuals > A4 Cabriolet Mk2 > Heating, ventilation, air conditioning system | Auxiliary heater | Aux. heater/heater booster | Diverting fuel for auxiliary heater | Diverting fuel (for auxiliary heater) from fuel tank | Front-wheel drive vehicles (2.5 l diesel engine Model Year 2002 only, refer to notes)

Front-wheel drive vehicles (2.5 l diesel engine Model Year 2002 only, refer to notes)

The fuel for the auxiliary heater is drawn in from the fuel tank by way of the connection -A-, the corrugated pipe -B- and the angled riser -C-.

Note

t	In Model Year 2002, the fuel delivery unit for vehicles with 2.5 l diesel engine was gradually converted to the same version as for the other front-wheel drive vehicles (supported on bottom) → Chapter and → Fuel supply system; Rep. Gr.20.

t	To stop any deposits on the bottom of the fuel tank being drawn in by the auxiliary heater metering pump, the riser -C- ends approx. 20 mm above the bottom of the tank.

t	To prevent the fuel tank becoming completely empty in auxiliary heating mode, the auxiliary heater is no longer activated by the control unit in dash panel insert -J285- if the fuel gauge is in the “red zone”.

The angled riser -A- must be installed as shown in the mount -B- of the bottom part of the reservoir housing and engaged.