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Hi all,
I have a W288 eco which will not power up and I have read every post I can find from others. It lost power partway through a wash.I have 240v at the Mains Filter output.
On the control board I found R2 blown and sent the board to QER who replaced that resostor and the LNK304 chip. This has not resolved the problem.
There is 240v ac to the main board but nothing at R2. I’m very limited in what I can faultfind.
Assuming I don’t want to scrap the machine:
a) Is there anything else I can do before ordering a new board? (£209)?
b) Is there anyone in the Oswestry/Welshpool area who services these? Local firm Beauclerks say no.
thanks in desperate anticipation
are you getting power to the board ?
I assume QER checked the board powered up so you should have 12v or os on the board on the chip outlet
dont know what R2 does so cant comment but it may be volts dc. a lot of the time there is a resistor that blows on boards when the lnk chips fail. i would ecpect this resistor to have 240v ac going to it unless its on the neutral side
DaveThanks Dave.
There is a connector clips onto the large board from the mains filter. and I measured 240v ac on that, so board has power and I picked up 240v at several other points on that board ( there are some large “blocks” on that board). However it does not make it as far as the R2 resistor (33ohms) which is connected via a cable to the small board ( the LNK chip and on/off switch are on the small board).A ribbon cable also connects the large and small boards. Though labelled 16v on one pin, I measured 39v dc there. That voltage was steadily dropping.
The replaced chip is bottom right.
Original was
LNK304GNReplacement
LNK304PNdatasheet shows the difference is just the packaging.
ok seems an interesting circuit
we need to see whats going on. seems like the board contains 2 circuits one to energise the other but cant be 100{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} as its difficult when your switching pics to try and trace tracks
for this circuit to work we need 240v ac to be rectified and smoothed to get about 320v DC there should be 400v caps on that board and you need to see if you have those voltages present
the output from the board on the grey wires shows 16v and 5v DC this has to be measured and to do this you need to find the negative which many be the next pin
Dave
please be careful as your dealing with dangerous voltages
Just to show you the main board in full.
You can see a thickish black cable beside the resistor ( which is 33 ohm and labelled R2, this was replaced by QER). That cable is ( I think) what should carry current to the small board. But there is 0v at that cable.
When I test the pins on the back of that ribbon cable you saw on the small board I get 39v dc where it should be 16v and I get 0v where it should be 5v. There is a GND connection as you said on the first pin.
The problem is that even if I found another faulty component it would have to go back to QER to repair. Another £55
Im at the stage where I will buy a new control board ( I’m loathe to scrap the whole machine) but just want to make sure there isn’t something else that will damage it. All I can see prior to the board is the mains filter which has 240v output. Could there be something faulty “downstream” of the control board which will damage the new board?
Or can I replace the control board with any confidence that it will sort the problem?
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