hi i have a bosch dishwasher type SGS45E02GB with a electrical fault ie the waste pump is not turning off when it should does anyone know which relay on the pcb is for this pump i've checked everythink else impellor/water in base & all are fine the only way to use the m/c is to turn it on wait for the water inlet to open then give the front of the m/c a sharp knock & the pump turns off we have to do this 3/4 times every cycle its now annoying can anyone help please 