ISE 10 W256W (ASKO WM70.1) won’t turn on

[flannel]

Hi, has anyone got one they could send me to help me diagnose a fault? I have the sheet with the resistance values that comes with the machine but it doesn’t cover the board resistors.

[iadom]

The workshop manuals do not go down to board level schematics or component values.

[flannel]

On opening the machine, I found a sticker stating ASKO WM70.1 and the service manual can be downloaded for free at manualslib.com

[iadom]

The official service manuals only contain the same circuit diagrams as found on the sheet in the machine. Like 95{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} of domestic appliance manuals they do not include circuit board component information.

[flannel]

Can anybody please offer any guidance with the following problem.

The power button doesn’t work but when turned off at the socket, left a few seconds and turned back on, the lights briefly come on.
I’ve checked the resistances on the circuit diagram* and they are all correct. (I thought the thermistor might be bad as it measured 7.9k whereas the range is 3.8 – 6.1k. However, the manual** shows the resistance increases at cooler temperatures e.g. at 10C, the resistance is given as 9.6k and my kitchen is fairly chilly).
I’ve checked all the resistors for continuity and there is no sign of overheating.
I’d be up for swapping out some components as a new control board would be £200 (from this site) but it’s risky as it might not fix the problem and it’s 7 years old so it may not last much longer mechanically. If I have to get a new machine, I’m tempted by the £500 EBAC with a 7 year warranty.

* The circuit diagram is supplied inside the machine – I found two errors on it:
[FONT=”Calibri”]1) The wire to EL is the bottom contact in the plug, not the one above it as shown.
2) The wires to AP go into the forth and fifth contacts from the top of the plug (not both into the fourth as shown).
For completeness, the resistance for F is measured across the black wire connections, not the blue and brown wire connections.

** The ISE 10 is the same as the ASKO WM70.1 for which the manual can be downloaded for free on manualslib.com[/FONT]

[flannel]

Picture of board and reverse (flipped to match) here: https://imgur.com/bXX7t05

[flannel]

Photo of whole board: https://imgur.com/k0bljGH

[electrofix]

with the way your machine is reacting my first check would be to see if the power supply chip is working ( 7 leg chip )
converts 300v DC to around 12 v dc for the board. you would need to check the output voltage and see whats going on

beware of the 300v input voltage as you can imagine its dangerous

Dave

[flannel]

Dave, the chip is a Power Integrations LNK363PN for which the pin-out is shown below. Am I correct in thinking that the 12V measurement should be made with the black test lead connected to the source (S) and the red lead connected to the drain (D)? If not, please advise as I don’t want to cause a short.

[flannel]

The last post does not show my picture but basically, the D pin is the odd one and the S pins are the 4 at the other end.
Datasheet here: http://www.farnell.com/datasheets/10058.pdf

[electrofix]

as you come out of the chip you normally find low voltage smoothing capacitors. thats where you measure it, across the caps

Dave

[flannel]

Dave, I’ve get the following voltages when the power is switched on at the wall (remember the power button on the machine does not function).
With reference to this: https://imgur.com/qVsABFx
Cap A = 320V
Cap B = 106V
Cap C = 5.8V
Caps A and C retain the voltage after the lights go out. However, the Cap B voltage drops and oscillates quickly between about 7 and 40V.

When it was working, the power switch had to be held for a few seconds before the machine turned on – almost like it was performing a check or waiting for something to warm up.

[electrofix]

well the output at 106v is very high. too high for the board so it must be dropped again somewhere to 12 and 5v possibly

there is another electrolitic to the left under the plug whats that reading ?

Dave

[flannel]

I’ve taken all the capacitor voltages, see here: https://imgur.com/Hqwo9YQ (Bracketed values are fluctuating values after the lights go out)
I forgot to label the power switch – it is the connector in the bottom left corner.

Thanks, your help is much appreciated,
Dan

[electrofix]

well dont know where to go now. You have a range of stable voltages which seems to rule out power supply

check to power sw is functioning and securely conected

the cap on the left with 0.6v seems a bit low but may get higher when board goes into operating mode

Dave

[Author]

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