LG WM-1280FHD

[Phidom]

Machine is dead apart from a couple of LEDs which stay on all the time regardless of what buttons are pressed. Pressing 2 buttons together can also make the 40 degree and 1000 rpm buttons come on just while they are held down. If it’s the main board the machine is BER. If it’s the control PCB it is worth doing. Has anyone seen this fault on an LG? The control PCB looks like it has got damp at some stage. I did have a go at one joint which looked like it might be dry but it didn’t help. The main board is embedded in silicone so I can’t look at the back of that.

[leavemetogetonwithit]

Re: LG WM-1280FHD

Do a conductivity test on the tactile switches. Attach the ohmmeter wherever you can find something you can get your clips on and then press the buttons while watching the display. Any hint of intermittency on any of them, replace tactile switch. With the damp atmosphere they corrode internally. If you’ve never done it yet, take one apart and you’ll see what I mean.
I had one acting strange like that in just such a situation and as it happens it had a sizeable burn mark on the main pcb, too. I endeavoured to dig into that jelly but gave up after half an hour getting nowhere. The thing is still working and that was about six months ago.
Mike.

[Phidom]

Re: LG WM-1280FHD

Thanks Mike. I did wonder if it could be a button. They are probably multiplexed somehow, hence the odd effects when you press 2 together. I wonder if Hotpoint ones fit?

[Phidom]

Re: LG WM-1280FHD

The machine is in my workshop so I can work on it at my leisure. I checked the buttons and found the on / off one high resistance. The Hotpoint buttons don’t fit as they are surface mount so I didn’t have a suitable spare. I pinched the “time delay” one, on the basis that you should still be able to work the appliance without it. It’s still not working, although now I only have the 95 degree LED lit all the time. I’m now wondering if I should have soldered wire links in place of the switch I removed. They have 4 terminals but are only single pole. It could be the board relies on the continuity within pairs of switch terminals to complete the circuit even when the switch itself is not being pressed. I suppose I might adapt a Hotpoint button by soldering on wires but I’m thinking that is one bodge too far!

[leavemetogetonwithit]

Re: LG WM-1280FHD

I think these would fit but check dimensions.
Must be something else you could do while waiting for them to arrive. Have you swept the workshop floor? 😆
Mike.

[Phidom]

Re: LG WM-1280FHD

Thanks again, Mike. They are certainly cheap enough 😯 . Better than £62 for a new board.

[Phidom]

Re: LG WM-1280FHD

Well I got the board out again and checked all the buttons again, all OK. The continuity is not required from the one I removed as the pairs are joined also on the PCB. I’m therefore back to square one. 🙁

[leavemetogetonwithit]

Re: LG WM-1280FHD

Sorry to nag but I’d still be suspicious of the switches. Have you tried working them a bit following a squirt of Servisol? (Could be cheaper from Connect)
It’s amazing how testing things doesn’t always show faults which the electronics themselves will find. Have had this with many a relay for example which tests perfect but won’t work when actually in circuit.
If not then you’re really down to component testing the rest of the board with about one chance in 50 that you’re going to find anything.
Remember that the bearings on LG always go after exactly seven years of family use so, if they haven’t been done yet, your customer is in for further expense a little way down the line.
Mike.

[Author]

Posts