Table of contents: Removal the circulation pump "V55" ↓ Installation ↓
Removal the circulation pump "V55"
Note. Depending on the vehicle equipment, the circulation pump V55 is also controlled by the auxiliary heater control unit "J364" if a request has been sent via the data bus system from the relevant engine control unit or the control and display unit, Climatronic control unit "J255". Since model year 2010, the start/stop system has been offered as an additional equipment for certain engines for this vehicle. On such vehicles, the correct design of the climate control and display panel, the settings of the Climatronic control unit "J255" and the auxiliary heater must be taken into account. On vehicles with the engine start/stop system, the circulation pump V55 of the auxiliary heater receives control signals from the auxiliary heater control unit "J364" during the stop function. The request to turn on "J364" comes from the climate control and display panel, Climatronic control unit "J255" installation via the "V55" data bus. The "V55" circulation pump is connected to the hose harness of the independent heater. When removing the "V55" circulation pump, press, loosen and disconnect the coolant hoses only on the "V55" circulation pump, so that you do not have to remove air from the entire engine coolant circulation circuit later.
Ignition (and an autonomous heater) switched off. Release the pressure in the coolant circuit by opening the cap of the expansion tank of the cooling system. Remove the front right wheel. Remove the front right mudguard. Clamp coolant hoses "6" and "8" (e.g. with hose clamps 0 25 mm "3094"). Loosen the clamp clamps "5". Disconnect coolant hose "6" from the circulation pump "V55" "2". Loosen screw "3" and remove clamp "7". Remove circulation pump "V55-2" from coolant hose "4". Disconnect electrical connector "1" from circulation pump "V55" and remove the circulation pump.
Installation
Installation in reverse order: the new circulation pump "V55" with an empty coolant circuit can only be switched on after filling the coolant circuit, since running the new pump dry can lead to its failure. Since little coolant flows out during the above-described removal of the circulation pump "V55", the liquid after removing the clamps from the hoses (additionally remove the cap of the expansion tank) flows into the V55 circulation pump quickly, so there is no risk of damaging it. Connect the electrical connector to the V55 circulation pump only after removing the hose clamps (and filling the coolant circuit). Remove air from the coolant recirculation circuit.