Dishwasher crisis!!! please help, hands getting very dry

Hello,

I wonder if anyone can point me in the right direction. Firstly I have a Bosch sms 6502/07. I was given it about two years ago (therefore I have no manual).
However just recently it has been causing the home fuse box to trip out, usually when I open the door there is still water in the bottom. I have checked the plug fuses and the socket fuse, all is working fine. Sensing a possible loose connection as the on light comes on and off when the door is opened, (this may be normal I can’t remember!) I took the front panel off, I could see nothing obvious wrong, I have an electric tester, but I’m not sure I’m putting the little sticks in the right place, but when I checked the switches they read 0 (which I think is right????) I also to the sides off and looked to see if anything had obviously blown but ……. to no avail. Anyhow after I did all this it worked for half a cycle and then cut out again at the draining stage. So has the pump gone weird?? Have I done all I can do and should I call a professional in?? and if so how much should they reasonably charge?? and is all this worth my while or should I just invest in a new one!????

I really appreciate any help.