Questions about: vacuum hose, pump, temperature sensor, intercooler fan

The old bridge has a Temp-feeler but I did not find a free plug there. However, it can also be that the wire harness was also changed because I got a tree. What does the loss of the sensor mean?? On the right side of the engine compartment there are two black vacuum hoses at the top of the spray wall. E the two go under the cover of the suction bridge (connector) and then where else. with me the end of the line hangs freely around. Where does it belong??? In the small fuse box (motor room) the fuse for the charging air cooler fan has burned down with me, so that I had changed the fan after a short check. That also fits to the temperature problem. Now it is unfortunately that the temperature on the track still rises and that the fuse still burns. What hangs the In order to check the pre-shipment pump I unscrew the silver lid in the trunk and then alternately remove the hoses there. Neither at ignition, has glowed, nor when starting came from one of the pipes diesel. Was this the correct test, the VFD sits under this lid? Further questions about the VFD should then possibly jmliff put. Gruss Saje