Bodge up

Got the caravan out to go through everything before we go off on Wednesday.
Mostly ok, but the toilet flush pump wouldn’t work. Much checking with the multimeter but no volts. Foray on the internet and Thetford’s manual was no good either. Tried to check the pump by using a small 12v battery and succeeded in getting a puff of smoke from the circuit board. More chasing on the web and discovered there is a fuse in an almost inaccessible location. Got it out and it was blown, put in a new one and we now have volts but push button still inoperative. Final resort was to bridge out the circuit board and fit a simple push button. This will do for now until I get a new circuit board at £53!!!!