Miele W844 EL200C Red Lights Check Inlet and Check Drain

[smcuk]

Hi All,

I have a Miele W844 with a EL200C board fitted

My machine keeps stopping during the cycle with a Red Flashing Light “Check Inlet” OR a Red flashing light “Check Drain”.

This does not happen every time, maybe 50%.

I have removed the EL200C board and checked the T 6,3A Fuse which is OK and I have tested the two relays OMRON G2RL-2 and SCHRACK RT114012 by passing a current across them and both give an audible click (the OMRON is a bit quieter)

I have also measured the resistance on the Motor across terminals 3 and 4 and this shows 3.4 Ohms. I haven’t actually inspected the brushes.

I have now exhausted my options and wondered if anyone else may be able to suggest something ?

Thanks
SMc

EL200C

• smcuk
• 11 Feb 2015
• 1

Two relays by the circular cut out are Black Omcron G2RL-2 and Orange SCHRACK RT114012

 

[yardie]

Did you check for continuity on the relay switch as it flip flopped?

 

[smcuk]

No, I didn't, can you give me an idea of how you would make that check ?

Thanks
SMc

 

[yardie]

Connect meter probes to the switch contacts on the relay. Meter set to lowest ohms range. Apply your 12v to the relay as before.
Just because you hear a click doesn't mean the switch inside is making contact.

 

[smcuk]

I have tried what you suggested. It appears to read around 4 ohms across two of the contacts until I apply the 12V. After this, the reading reverts back to start value of 1.

Note, Black Omron G2RL-2 has 6 connections while RT114012 has 3

Black OMRON Relay
4 Ohms between connections 1 and 2 - When 12V applied this resets
4 Ohms between connections 5 and 6 - When 12V applied this resets

Orange RT114012
4 Ohms between connections 8 and 9 - When 12V applied this resets

Numbered Contacts

• smcuk
• 12 Feb 2015
• 1

Untitled

• smcuk
• 12 Feb 2015
• 1

 

[yardie]

PLEASE IGNORE THIS RESPONSE!!!
So when no voltage applied across pins 3 and 4 (actually 1 and 8, see datasheet) the switches between pins 1, 2 (actually 2 and 3) and between pins 5, 6 (actually 6 and 7) are closed cct (continuity).
When 12v applied the switches open cct (no continuity).

Thats correct, as you would expect!

P.S. pins 4 and 5 are not being used on the Omron relay.

 

[yardie]

I am curious as to why you have headed directly for the control board?

Check heater
Check water inlet solenoid
Check motor, ok so you have done this one!

Pipes clean, filters checked, reservoirs clear, waste pipe and waste clear.
Water pressure low

How is the waste pipe connected to the waste, is washing machine on too when it fails.

Drain pump failing, not as powerful as it used to be so resistance in the 'U' bend from having tap on or wm pumping out at the same time causing dw not being able to overcome the others higher pressure.

 

[smcuk]

Good points,

It was confusing because the problem started with occasionally displaying the "Check Inlet" Red Light and then stopping. If I restarted the program it would most likely be OK.

I then checked the inlet water supply which is about 3 Bar and removed, cleaned and replaced the inlet filter but there was always a decent flow of water into the washing powder compartment so I ruled this out.

I also once got a flashing "Main Wash" orange light and a flashing orange "Drain" light

Then it started sometimes displaying the "Check Drain" red light and stopping so I checked and cleaned thoroughly the drain filter.

At this point I thought the completely different lights were a red herring as it seemed unlikely they were all related.

I then studied other cases on this forum and quickly saw a repeating pattern of many other Miele owners with a faulty electronic board which could be repaired.

I then assumed from the forum evidence that all these warning lights were either the brushes or a faulty relay on the board and focussed on these options.

I removed the brushes earlier this evening and there is still nearly a couple of centimetres left on each of them so they can be ruled out.

1 - Have not checked heater apart from the water is normally warm before it stops
2 - Have not checked water inlet solenoid apart from water can always be seen pouring into the powder compartment before it stops.
3 - Inlet pipes are OK
4 - Have not checked Outlet Pipe
5 - Inlet and Outlet filters clean.
6 - Not sure what the reservoirs are ? Where Washing Powder is added ? That is clean.
7 - Water Pressure 3 Bar
8 - Waste Pipe is out through a plumbed u-bend which has worked OK for 13 years.
9 - Drain Pump seems to work OK and drains all the water out, but at that point where the machine normally starts the spin cycle is where the "Check Drain" red light then comes on rather than start the spin.
.

 

[yardie]

Pressure switch?

Something else to consider, dry joints on relay pins or other solder joints on the board.

Loose connections from machine vibration. As well as worn tracks that the plugs connect to, usually reflow as a good measure But this is with plugs that push directly onto pcb board, you have connectors on your board.

Put some good quality well focused photos of both sides of the board on here so I can see if anything looks odd.

Is this the only board on the machine other than the front fascia control board? Though that may need inspection too!

 

[smcuk]

Yes this is the only board except the fascia..

images of board top and bottom attached...let me know if these are good enough to see...

thanks

Untitled

• smcuk
• 13 Feb 2015
• 1

Untitled

• smcuk
• 13 Feb 2015
• 1

Untitled

• smcuk
• 13 Feb 2015
• 1

Untitled

• smcuk
• 13 Feb 2015
• 1

 

[yardie]

The photos are very good!

Not much to say other than visibly everything looks good, nice clean board, so signs of arcing/burning/heat, solder joints look good but closely inspect them yourself, they will be obvious on very close scrutiny.

Not alot to test on here other than the relays, perhaps test each one say 20 times or so just to be sure each one is making contact everytime.

What is the known common fault on the board?

Whats under the heat sink?

You might want to just check the 2 solder joints on the Omron relay in 3rd photo (bottom two) hard to see in photo so could be fine.

 

[yardie]

Now having seen both sides of board I see that the Omron relay has the coil pins to the far edge of the board and all 8 pins are in use.

When testing you need to have your meter probes on, according to your photo, pins 2 and 3 then on pins 4 and 5.

When no voltage applied to the relay coil, pins 1-2 and 5-6 are making contact, when 12v applied the switch operates and pins 2-3 and 4-5 are making contact.

Re-test the Omron relay.

 

[smcuk]

Ok, you are correct, I have re-tested the Omron about 100 times on all the combinations. Sometimes it appears as though the reaction on the meter is a bit slow, other times it seems to work OK. It is hard to tell if the relay is not working or my connections between the pins was not perfect.

Overall I think the thing is working OK I am just trying to find fault with it...damned thing.

 

[assuhors]

Remove and clean the pressure chamber,the part with the rubber tube coming off of it.Located on the drum above the heater.

 

[yardie]

Not sure location on yours but yes has small bore hose/pipe coming from it.
If its a simple mechanical switch you can blow into it an hear it click open /shut.
Meter test as you do it.

How many pins are on it?