Bosch dishwasher not filling with mains water

Hi,

We have a Bosch Excell SGS43A12GB-27 dishwasher. Bought s/h from a charity shop, it had been PAT tested etc. Upon install I ran a Finish cleaning bottle through it and I believe it worked - bottle had got rid of it's contents etc. But then ran a wash and everything was still dirty.

Listened and fiddled and deduced that no mains water was going in though sounded as if pump was running. After a bit of a trawl round the net I decided to brave it out and got the toolbox from the cupboard.

Drained the waste and fresh water from the bottom first off and cleaned any muck out of the waste area. took the kick panel off which was a real bugger. Especially as there was nothing behind it!

Then removed the side panels. All looks well inside with no wires off, burning etc. On the side with the distribution tube there was some condensation in the tubes and black residue in the top left chamber but nothing seemed untowards. Both microswitches were free and moving.

Ran the machine with no sides on a rinse cycle. No water came into the distribution tubes at all, so switched to a main cycle whilst it was running - nothing again. So I put a meter over the two terminals on the mains inlet solenoid and there seems to be no current to it - just the odd, millisecond long pulse on a sporadic basis.

So my question is what gives the current to the solenoid? I'm assuming it is the fault not the solenoid. And also when I was checking the solenoid terminals and switching the machine on and off, the pump (which was always running when the machine was powered up) started sounding very rough. Have I ruined it by running it after draining the water tanks in the bottom?!

Many thanks.

Bit late but I will try to answer some of your queries:
Usually there is an insulation mat behind the kickplate, this has to be removed to get to the pump. It is easier to remove the outer door to do any work via the kickplate as the door restricts access. To get the door off take out the T20 torx screws on the sides (3 each side).
The inlet valve gets voltage via the PCB (you will see the base of the PCB sticking out underneath the panel facia if you remove the door).
There could be several causes to your problem. If the pump runs constantly the flood safety device has been activated by leakage onto the bottom plate & as long as the flood protection device is active no water will enter the machine. If it is only a fill issue one of the following is usually to blame: blocked pump/drain hose, faulty Aquastop, faulty pressure sensor, or PCB fault. If the pump sounded "rough" it may be defective or have a piece of glass wedged in the impellor. If the machine has not been used for a long while the circulation motor impellor could be jammed.
I am afraid you'll have to dig a little deeper in the interim but I'm sure with a little patience & help from other good souls on this forum you'll resolve the problem.

Hi Zipper,

Thanks for your reply. The panel behind the kick panel seems to be just a solid bit of metal. I'll remove the door and have a better look but it seemed pretty substantial and immovable when I was working on it!

I assume the safety valve is worked off the float in the base? In my machine this was connected by a red rod to a micro swith - microswitch was off but working, float was dry and rod moved freely. I think this was all ok.

Of the possibles you noted where are they located? and what is an Aquastop?

Many thanks,

Peter

Aquastop is a grey box under the brass nut that screws onto the water supply. But I just looked at a drawing of your machine & it doesn't appear to have one. The inlet valve on your dishwasher is located behind a small plastic panel at the rear of the machine (where the supply hose enters).
You could check the resistance on the inlet valve, it should read 3 - 4kohm. If you have continuity on the valve could you could try taking off the 2 spade connectors & hotwire the valve with 230v to see if it functions mechanically & allows water to enter. But be extremely careful, electricity bites!
If you take off the door you will see 2 torx screws high up on the kick plate, take these out & lift away the whole plate. Once off you will see the pump & other components.