NEFF Dishwasher on/off light will not come on

Goreme

Hi there. I have an 11 year old Neff dishwasher. The power light will not come on on the Control panel module. There is power to the unit, as when I manually lift the floater (mushroom shaped device on the bottom of the inside of the unit - that opens when water is in the unit to empty the unit) I can hear the pump trying to pump. I have taken out the Door Latch three way switch and checked it out with my multi-meter, and it is fine. I have checked all the connectors for loose wiring. I have also taken off the side panel and checked that the side drain tubes are also clear. I have also checked that the water inlet filter is also clear.


That leaves the control panel module itself as the cause - unless anyone can suggest anything else? I have got the part number and price from NEff/Bosch, and its E113 (or £84.60 online delivered to Belfast Parcel Motel).

Since I am not certain it is the control panel, I am wary of jumping in and buying it. Does anyone have any suggestions as to what else I could check before i buy the control panel. As I said, the on light will not come on the control panel when I push the on/off switch.

Since this is an integrated dishwasher, its a bit of a pain to replace, as it fits into the kitchen units, etc, so it would be good it I can repair it myself before we go out and try to match up with a new one from a shop.



Does it sound like its the Control Panel Module and is there any additional checks I can do to confirm that its the cause of the issue?


Make: NEFF ENR No. S5444X1GB/23
FD No. 8704

Control Panel Module Part is No. 00498513.

The Red Ace

check the wiring harness at the bottom of the door, when they get older and brittle it is common for to get one or two wires broken from continuous opening/closing of the door. If you find the problem there splice it with new cable well back from both sides of the breakage

Goreme

I replaced the Control Panel Module and the buttons lit up as normal on the replacement part - good stuff!! I followed the reset procedure for the Control Panel Module and all was good. I then set the dishwasher to start. However a few minutes later I noticed that it wasn't washing. I opened the door and the tap icon was lit up. I then remembered that I had not turned back on the water supply at the valve. I turned this on, but could still the tap error light was there. I then did another Control Panel Module reset, but the tap error remains on. I the re-checked the valve inlet filter, and it was clean. Turned the valve back on again. I can feel the solenoid at the valve inlet buzzing but I don't know why the water is not coming in.
Is there a special way of re-setting the tap error light/icon on the Control Panel Module?

The Red Ace

if your machine has a valve with a diaphragm with a narrow hose attached remove the hose and press on the diaph with a pencil or likewise it may have a blob of water preventing the valve from opening, if it has a second valve also at the tap end of the hose that could be causing the problem, it will be one type or the other, you should also check the aqua float switch located in the centre of the base to see that the aeroboard that activates the micro switch isn't dislodged

Goreme

The Red Ace wrote: »

if your machine has a valve with a diaphragm with a narrow hose attached remove the hose and press on the diaph with a pencil or likewise it may have a blob of water preventing the valve from opening, if it has a second valve also at the tap end of the hose that could be causing the problem, it will be one type or the other, you should also check the aqua float switch located in the centre of the base to see that the aeroboard that activates the micro switch isn't dislodged

Hi Red Ace,
Thanks for the suggestions, I'll try them this evening when I get home.
Is the "valve with a diaphragm with a narrow hose" also at the tap end?
I have checked the "aqua float switch" a few times underneath the machine, and it does seem to be working ok. I can hear the micro switch going on and off when I reach in with a wooden spatula and life it up and let it back down again. Also when I put a few jugs of water in the machine, the floater inside the dishwasher rises and the drain pump comes on and starts draining the few jugs of water.
And as I said, I'll try your other suggestions this evening.
Thanks.

Goreme

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Hi Red Ace.

I checked that aqua floater switch under the machine and it works fine. When I manually lift the aqua floater switch the pump comes on, and when I drop it, the pump stops.

Checked the filter at the water inlet. Took out the little filter and checked that its clean. I also checked that water comes out of the valve itself when the dishwasher water connection was removed.


1.     Checked for kinks in the line – no kinks.
2.     After removing the machine side panel - checked for any visible blockages on the side machine in the piping – no blockages.
3.     Reset using the instructions the Control Panel Module once again and still the tap error appears.
4.     Checked where the water goes out at the bottom of the machine, and its not blocked there.
5.     Filled a few jugs of water  into the machine. The floater inside floats and the machine then empties. And goes out to the drain without any spillages.
6.     Took off the water spray arms inside the machine – they are not blocked.
7.     One thing I HAVE noticed however is that the solenoid inside where the water inlet hose connects to the house water supply – that this solenoid is humming because its swiched on. I have tapped this solenoid with a hammer, just incase it was jammed and the solenoid was not moving back when power was applied to allow it to take in water. Still I get the water tap error light.
8.     I have phoned Bosch/NEFF to ask if there is different reset sequence or code to clear that tap error light. But they said they didn’t have access to that information and that it would require an engineer call out.

You mentioned "if your machine has a valve with a diaphragm with a narrow hose attached remove the hose and press on the diaph with a pencil or likewise it may have a blob of water preventing the valve from opening," I don't see where this diaphragm can be. Is it located where the water inlet pipe enters the underside of the dishwasher?

Any more suggestions would be appreciated. Thanks.