Tim W wrote:
The Wise One
wibbled on Thursday 14 January 2010 22:20

This letter never seems to have arrived in the group the first time --
trying again. Sorry if you have seen it twice now!

Hi,

I have a Beko "DE 2541 FX" slimline dishwasher that stopped working
properly... just before Christmas.

When I press the button to start the cycle, the machine drains and
then fills as normal and then -- instead of kicking into that rhythmic
swishing sound -- it just sits there in dead silence. After 15 minutes
it might fill again, and if left might fill yet again after another
while. But it never kicks into wash mode. It does this even on the
simple no-heat, pre-wash setting.

I checked the heater, it looks perfectly fine and is not
open-circuit.

I checked the thermistor, fine, it correctly changes resistance
when it's in hot water.

Everything looks pretty much perfect, after all it's only three
years old.

The main circulation pump looks pristine, and so does its
capacitor. But when I measured with a multi-meter across the terminals
of the pump (insulated crocodile clips!), I discovered that at no time
does it receive any voltage.

I decided to replace the controller card (only £30) and today I
find it still has exactly the same problem with the new controller
installed. Argh!

So what is the real culprit? Can anyone help? I know there is a
circulation sensor, a thermistor, and various door safety and overfill
doodads but I am not sure what exactly would cause this particular
problem.

I would be grateful for anyone's experience and expertise: I don't
want to be defeated by this thing!

With many thanks,

Sandy

wild stabs in the dark

I thought about the water level sensor (machine thinks there's no water) but
as it apparently fills correctly, that suggests "a" level sensor is working.
Could it be the main sensor has failed but a backup one (or a second sensing
position on the main sensor) is preventing overfilling (don't know those
machines, so I don't know if there is any validity in this idea).

Have you tested the level switch which might be in several forms to see if
it's doing what you would expect?

Are there any relays on a supplimentary board or box somewhere?; thinking
the controller is doing its stuff, but the relay that actually applies power
to the pump has died?


My intuition says it is some sensor reading not working that is
stalling the dishwasher programme.

The big problem with Beko is that there aren't any servicing
manuals made available. (An operator at the UK Beko servicing place --
I think -- kindly let me understand that they *used to* make service
manuals available, but no longer.) So I have only a very nebulous idea
of what sensors and extra doodads the machine has, chiefly from
disconnecting it, turning it on it's side and taking off the bottom plate.

I have "The Dishwasher Manual" by Graham Dixon (Haynes
Publishing). It's not as helpfully written as I had hoped, but at least
it encourages one to realize that, yes, all these machines are basically
the same and fairly straightforward beasts.

However I have obtained the circuit diagram of my Beko dishwasher,
the logic of which was designed by the Turkish company 'Arcelik'. I've
scanned and uploaded the diagram he

http://i49.tinypic.com/28r1thw.jpg

Unfortunately, I can only partly understand it. I think it doesn't
help that at some stage, the character-encoding of the labels got
screwed up. (O digital Tower of Babel that we live in!) I'm guessing
that during design it was all Turkish, but now it's...not. Also, many
of the symbols in the diagram, I don't recognize.

Counting the pins from left to right, here's what I *think* is attached
to each:

pin 1 : main power button switch
pin 2 : motor with capacitor? dunno.
pin 3 : pump motor
pin 4 : motor (without pump?? a "load"?)
pin 5 : pump motor
pins 8-9 : God knows what
pin 11 : fuse, water-heater, normally-on microswitch
pin 12 : a normally-off safety microswitch (?)
pins 13-14: ???
pins 15-16: a normally-off safety microswitch (?)
pins 17-18: ???
pins 19-21: Thermistor circuit

Mysteries:
At the low left of the diagram, what is the symbol marked '6?
In the middle of the diagram, is the thing labeled &2 a two way switch?

I think if I knew these things, it would help to connect (in my
understanding) the diagram and the actual wires and devices I see dotted
around the machine. Maybe also it will confirm your suspicions/theory
about my fault?

I haven't been able to find this information about the circuit
diagram anywhere on the web, which is why I've now written here with it,
and put it up -- hopefully, someone who knows this stuff will be able to
help fill it in, and so it'll be useful to other people with these kinds
of problems in future...

... and of course, if it stops me having to wash up by hand every
day, that would be WONDERFUL!!!

With many thanks (again),

Sandy