Washing machine power module diagnosis

[acheckley]

Hi everyone. I bought a Servis M6011 washing machine and used it twice an now it has stopped working.

It exhibited the following symptoms:

Start --> Fill --> Stop

Power On --> Spin --> power lights flicker --> Stop

Power On --> Spin --> power lights flicker --> Stop

and full program.

Second wash was the same process.

Now the spin cycle won't begin.

I've checked: motor brushes, door lock, pump filter. Everything works fine (fill, drain, cycle timer etc) except the spin. The motor looks good and most of the parts look quite new. Would this likely to be the power module?

Thanks,

Andrew

 

[rocks1]

Did you buy it new or secound hand The bad news is servis went bust 2 years ago no parts around no service agents wots left will be very expensive

 

[acheckley]

Hi, I bought it second hand. I'm not so worried about the parts, since QER repair PCB's quite cheaply (found on ebay) and I've seen other reasonably priced parts around the internet.

I'd like to follow the PCB route if I can get enough information. Judging by the powering off and power light flickering when starting the spin before it stopped working, I'm trying to work out the specifics of this symptom. It's power related, but would it be the power module, motor or something else? Is there a large capacitor that needs replacing, a speed control module? or something else that typically goes in these machines?

Thanks,

Andrew

 

[Leccy758]

First thing I do on a servis machine is check the PCB's for bad solder joints, bad connections or arcing particularly on the motor speed control board

http://www.emwelec.co.uk/index.php?action=item&id=39&prevaction=search&previd=&prevstart=0

 

[acheckley]

Thanks, I'll have a look around.

I'm not quite a beginner with electronics but I've always stayed away from capacitors. Other than the main board, are there any others I should watch out for?

I have two leads with discolouration near the device for the power module.

Looks like a little burning around there.

Would it contain any caps in this part?

Thanks,

Andrew

 

[acheckley]

Ah, actually, it's not the power module as such, its a little device towards the top of the machine where the power-line comes into the machine.

 

[zipper]

I have a feeling you may be describing the interference suppressor. Post a picture so we can see.

 

[acheckley]

Hi, I've located the problem. The motherboard has a bit of burning on the back. Looks fixable. I want to get the board off to one of the companies that repair the boards.

All of the cables have come out except the data cable connecting to the front panel. Does anyone know how to remove these cables? Are the plug/or soldered on?

Thanks,

Andrew

 

[Mickymoody]

As you have partially removed the board, you tell us if it's soldered or socketed! If its a socket, they usually have a clip to hold it in place, or look at the other end of the lead, to see if that's removable.

Sounds like a faulty thyristor, or voltage regulator, they can dry out capacitors near to them, so see if there is any ballooning on nearby caps, to prevent you being shocked by one.

The high value caps 400-600v, if there was a primary psu fault, and they couldn't be trusted not to hold a charge, we used to short them out with an insulated screwdriver, got some mighty cracks, as they discharged, better a screwdriver than me! There is a tool available that plugs into the mains, and you touch the caps legs, and it discharges, the device used to vibrate when it discharged them.

 

[acheckley]

Hi everyone.

After looking at the board, I noticed that the tracks had blown from one area to another. Therefore, I've decided to solder new tracks.

I'm pleased to say that this has worked. I bought some appliance wire from Maplin and joined the missing tracks.

After slotting the board in, the machine is as good as new. Except for the anti disturbance filter, but I'll start this in another post.

Thank you for your help.