Coolant circulation pump (VW Sharan 1)

The engine cooling system has an additional electric coolant circulation pump. It is designated as V51 in the wiring diagram. The circulation pump runs continuously and also cools the engine after it has stopped, so that a hot engine continues to cool for some time after the ignition is turned off. In this case, as usual, carry out the appropriate check of the condition of the hoses, hose clamps, etc.

Check the functionality of the additional pump, as well as turn on the fan after stopping the engine, in the following order:

Attention! When checking the functionality of the additional pump, the ignition must be turned off.

• disconnect the four-pin connector (Fig. 196) of the fan temperature sensor from the thermostat housing;

• connect contacts "1" and "3" using a piece of wire (brown-red cable and brown-yellow cable) (Fig. 197);
• the cooling system fan and the coolant circulation pump should start working;
• if the fan and circulation pump do not work, then there are other problems that must be identified at a Volkswagen service station using appropriate measuring equipment.