Miele dishwasher stop starting then all lights start flashing

[lightbeing]

Hi,
This was my xmas present, our Miele dishwasher G1040 starts fine, fills, empties & water circulates fine and after 5 secs from when the water starts circulating it stops then after 5 secs starts again and it keeps doing this stopping starting sequence for about 5 mins and then stops with all the three lights flashing (wash,drying,End) any clues please? I have checked the obvious ( no leak, clean filter, etc)
Many thanks for your help.

 

[Echo the husky]

The user manual states that this fault code means there is a technical fault. How unhelpful!

 

[RichardMNZ]

Does the WASH light flash in sequence with the others or does it flash a pattern. Please watch. It is helpful if it does in that it is used to identify the type of problem.

 

[lightbeing]

Richard - All the three lights flash together (no pattern) - thanks.

So far I have tried the following with no success
I have tried to read the fault code but it appears that there are none! Unless I am incorrectly accessing the fault codes.
I have checked the control board, the PCB looks pretty fine no bulging electrolytic caps or bad solder joints, etc. but still suspected.
I have inspected the heater relay, the contacts had heavy contact surface oxidation, so I have cleaned as much as I could with contact cleaner spray and cotton buds.
I have inspected the heater pressure switch and it appears to be working, on blowing the port I hear the clicks and able to measure the continuity as it switches between the poles.
The heater coil within the circulating motor measures a reasonable resistance.
I am now suspecting the control board but it is an expensive part if the fault is somewhere else.
Would be very grateful for any sound suggestion.

 

[Echo the husky]

Is this model fancy enough to have flow sensors going to the spray arms like the newer Miele models do. If the flow sensors are not detecting water flow after switching on the circulating pump, it might think the pump is jammed and is switching it off after 5 seconds.

P.S. Good work with the testing so far, it's nice to see someone get stuck in!

 

[lightbeing]

Hi Freddo - thank you for your input , there is a 4 wire solid state infra red diode/IR sensor (it is called turbidity sensor) located in the feed for the top spray, no other circulation water flow sensor in this model that I can find. Not sure what to investigate next!

 

[Echo the husky]

This sensor being blocked/faulty is all I can think of (other than the PCB), especially as the pump works for a bit. I moved from appliance repair to electrical work 10 years ago now so i'm probably a bit behind with the times!

 

[lightbeing]

Thanks Freddo, I'll try to see if I can somehow test or maybe bypass this sensor and give the right signal back to the board. We bought this DW new in 2006 and it is a shame to see it go.

 

[RichardMNZ]

Door shut
Dial at 12
Dishwasher turned off

Hold the start/stop button down and turn it on using the power button.
Press and release the start button 3 times but hold it down on the third time until the start/stop light flashes slowly.

Turn the knob to 1am and note the flash pattern. Press start/stop to see if there is more than one code. Press and hold start/stop it clear any codes.

3am is where you can test individual components

 

[lightbeing]

Hi Richard many thanks for your valuable input as it enabled me to read/clear the fault codes. There were 4 codes in total, the last three were from the distant past so I have cleared these and started a normal wash and got the current fault code which is F14
I understand that it indicates that there is a fault on the circulating water pressure measured by the heater pressure switch.
As I have mentioned earlier I have examined the pressure switch a couple of days ago and manually tested it by blowing and hearing it clicking and checking that it switched ok using a continuity ohm meter, so I am a bit baffled!
Next I will try to test the pressure switch in circuit to make sure that the control board is okay and the problem is indeed to do with the water pressure side.
Thanks again..

 

[lightbeing]

Hi
I have now tested the pressure switch in situ and measured its terminals on the PCB while the circulating pump was running and it was showing a faulty reading of around 120V AC, this should be 0V if the pressure switch is active and if it was working correctly.
The good news is that I have determined that the Control board is fine. I have located an eBay seller in Germany for the part and will go ahead and order it.
I will be attaching the circuit diagram, the technical manual that I have found today on the web and other photos which may help someone in the future.
Thank you all and wishing everyone a Happy New Year!

 

[lightbeing]

For some reason i am unable to add the images to this thread, so I have just added the links.
Circuit Diagram: https://goo.gl/RvsJcP
Pressure Switch:https://goo.gl/Qkrs54
Diagnosis: https://goo.gl/photos/NSvUyZvuS3QFwroEA
Technical Manual: https://goo.gl/yOHtLc
Cheers!

 

[Echo the husky]

Well done!

 

[bpowell555]

I have same and have ordered part 6996821 which is the new part for 6190703 stamped on the original. Will post how it goes. Slightly annoyed when I tipped the machine over the rinse aid leaked.

 

[privolen]

Fantastic, lightbeing your link-list made my day!
It happened so that my old miele 1130 was flashing all there yellow leds, first at the very start, then when i replaced the aquastop valve, after about 5 mins into the program. Then I found your link list with the plans and tec guide, and that led me to fix/replace the pressure switch and voila! The best came back to life. Thx a lot