Whirlpool washing machine board issue (MINISEL 600)

[otousama]

Hi there, I'm trying to fix an issue with my washing machine (Whirlpool AWG865) and its control board, namely a MINISEL 600 85SX-85DX-45DX (attached photos). The issue started with the machine refusing to accept a change in the washing cycle selection, it was stuck in cotton 60c and turning the potentiometer on the front wouldn't change the selection. Then after a few days in this condition it began to get high water temperatures and the board got a little charred near R54. I'm at a loss here, I did try to test some of the obvious components (capacitors, diodes, triacs...) but couldn't find a thing, maybe the culprit is the MCU?

To be honest repairing this board is nothing more than a challenge now that I've got a new machine, it's just the idea of getting screwed by a little resistor or cold solder joint that bothers me... Any guesses much appreciated.

[budm]

Re: Whirlpool washing machine board issue (MINISEL 600)

You have bad solder joints on that quick connector tab, you can see how poor the soldering works are on the bottom side of the board, I would re-solder all those tabs. Also inspect all the solder joints on that board.

[R_J]

Re: Whirlpool washing machine board issue (MINISEL 600)

Looks like supply voltage for the triacs goes through that connection (F10) so it could effect a few things

[otousama]

Re: Whirlpool washing machine board issue (MINISEL 600)

You have bad solder joints on that quick connector tab, you can see how poor the soldering works are on the bottom side of the board, I would re-solder all those tabs. Also inspect all the solder joints on that board.

Ooops... Re-soldered the quick con and almost all the other joints. Tomorrow I'll test it on the washer.

Looks like supply voltage for the triacs goes through that connection (F10) so it could effect a few things

Great! I couldn't find the schematics for this model. Now It looks like I can stop randomly poking around. Q2 has to be checked again I guess, the charred connector happened after i tested it.

Edit: Transistor tester recognized Q2 as a triac with Vf=.77V. It should be ok.

[R_J]

Re: Whirlpool washing machine board issue (MINISEL 600)

Looks like Q2 drives the relay to keep the door closed so you can't open it when its running. It is connected to the door interlock switch that connects F2 (a/c in) to F10, out to q3,4,5,6 etc

[otousama]

Re: Whirlpool washing machine board issue (MINISEL 600)

I tried to install the board, right after firing it up the interlock blocked the door and something inside the machine was making a hissing noise, didn't respond to inputs.
Then after examining the board and testing all the triacs I decided to leave no stone unturned and... test every single component.
The results were meh, C1 and C2 (100nF) measured 24nF and 44nF. Both X2 caps that I guess are for filtering and nothing more.

So, if the issue was the board, it must be a fried MCU, if it wasn't the board well... now it is.

[redwire]

Re: Whirlpool washing machine board issue (MINISEL 600)

The burned spade terminal (F10) I would check- even with a new board your wiring harness probably needs repair. It's a bad connection that is getting hot.

This kind of thing causes appliance fires, because there is no fuse when the PC board burns and carbon tracks. You can also check for product recalls.

[kaboom]

Re: Whirlpool washing machine board issue (MINISEL 600)

All those power terminals need to be resoldered. As well as triacs & relays, and power-carrying thruhole jumpers. Be sure to tighten up any loose terminals in the connector body with a small screwdriver. If oxidized, you'll need to reterminate that lead individually and cut the bad part of the connector body out of the way.

As for issues w/ reading inputs from the control panel, first clean those edge connectors (PCB lands) with your locally available equivalent of Caig Deoxit or CRC 2-26. The multi-position connectors also need a squirt when snapping them back to the board.

Whirlpool had many issues with dishwasher fires/recalls several years ago because of those same terminals & bad soldering.

Dishwashers made within the last ~12 years come with a thermal breaker positioned over the PCB, so when the terminals go bad & heat up, power is cut.
The soldering issues should've been addressed instead!

[otousama]

Re: Whirlpool washing machine board issue (MINISEL 600)

The burned spade terminal (F10) I would check- even with a new board your wiring harness probably needs repair. It's a bad connection that is getting hot.

This kind of thing causes appliance fires, because there is no fuse when the PC board burns and carbon tracks. You can also check for product recalls.

Yeah, those terminals got very hot. Before completely failing the washer was willing to start the cotton 60c cycle (only this one, that couldn't be stopped or modified) but then one time it got stuck heating the water till I noticed quite some time later and stopped working altogether.

All those power terminals need to be resoldered. As well as triacs & relays, and power-carrying thruhole jumpers. Be sure to tighten up any loose terminals in the connector body with a small screwdriver. If oxidized, you'll need to reterminate that lead individually and cut the bad part of the connector body out of the way.

As for issues w/ reading inputs from the control panel, first clean those edge connectors (PCB lands) with your locally available equivalent of Caig Deoxit or CRC 2-26. The multi-position connectors also need a squirt when snapping them back to the board.

Whirlpool had many issues with dishwasher fires/recalls several years ago because of those same terminals & bad soldering.

Dishwashers made within the last ~12 years come with a thermal breaker positioned over the PCB, so when the terminals go bad & heat up, power is cut.
The soldering issues should've been addressed instead!

Already tried cleaning the contacts, changed the ICs on the panel board and tested with a decade resistor box in place of the frontal knob, the one that let you select the washing cycle. The voltages on the pins of the MCU were changing while rotating the knob but the board was not accepting any input, only the start button was working, but once started you couldn't stop it, had to wait for it to finish the cycle.
I used the washer in this half-working state for a few days while waiting for my new machine, the charring of the connectors happened later on.

It was made back in 2006, had some minor issues during it's lifetime but after all it did its job for over a decade, oh well...

Thanks everyone.

[sam_sam_sam]

Re: Whirlpool washing machine board issue (MINISEL 600)

Those are the worst terminal block ever if the wires are not all way in the crimping part it will heat up like that

There is not much that you can do with the plastic holder it is to far gone
The only thing you can do is try to find out what series this connectors are and replace them
If you do find them buy the tool to install the wires in the connector for a good connection

I have work with type of connectors before they work but hard work with