there is something wrong with my central locking. when I try to open up my car (3 door corrado) the boot and the drivers door open no problem but the passangers doesn't. I can't even open the passangers door with the key now. the lock looks like it's going to pop up but then goes back down. I can't open the door to do any work. does this sound like the pump? if so where is it located. the car has the factory fitted total closure alarm and is a 1994 vr6.