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Hi,
This washer recently resorted to the following sequence:
Select cycle, turn on, then drum instantly and violently goes into fast spin. Move the selector dial anywhere else and the same thing happens. Originally the fault developed while doing a wash load, when it got to the drain and then spin cycle, it stopped with the drum full of water. When attempting to move the cycle on via the dial, it suddenly shot into full spin. Now it does this whatever setting it’s on.
It uses a control board with the ticking, timer-type selector (mechanical with stepper motor) and a sprinkling of components on the board, with one IC. I’ve checked the triac (ST BTB16 800BW) thinking it may have gone short, but it’s fine. I also checked the surface-mount transistor that switches the triac’s gate, but that’s reading fine too.
I know this isn’t a UK washer (it’s in Spain) but wondered if there was a general fault that causes this type of behaviour?
Thanks
Re: Bluesky BLF1011SP – drum stuck on fast spin
Hi
Check the motor wiring and the tacho on the back of the motor, the tachosdo come loose or fall off and this will cause motor to go into uncontroled spin.
Unplug before working on machine , and only test using a multimeter.
Re: Bluesky BLF1011SP – drum stuck on fast spin
Thanks for the reply. Is the tacho a small, circular plastic ring that has two wires coming from it? Looks like a ferrite core?
Incidentally, I forgot to mention that the drum will occasionally do a reverse fast spin after the forward fast spin, then the machine refuses to respond to anything.
Connected it back up today (fault started weeks ago and usnig spare washer now) and found it wouldn’t take water in, it just seems obsessed with going into a fast spin the moment it’s switched on, that lasts for 10 seconds or so, then unresponsive for a while.
Re: Bluesky BLF1011SP – drum stuck on fast spin
Hi
The tacho is a coil with 2 wires and other part is a magnet that should be attached to the motor shaft inside the coil . The magnet spins causing a current that the pcb senses,if the magnet is not attached to the shaft the motor will spin out of control.
Mike
Re: Bluesky BLF1011SP – drum stuck on fast spin
It’s a Beko-build, so tacho magnet is a good suspect.
Penguin45.
Re: Bluesky BLF1011SP – drum stuck on fast spin
Also worth checking the motor plug wiring harness, I have had two BEKO machines in the past fortnight with the wiring to the motor tacho broken inside the insulation, just were it meets the motor plug.
Re: Bluesky BLF1011SP – drum stuck on fast spin
Thanks for all of the replies. I did check the tacho was connected – I lifted off the plastic cage that clips onto the motor body, studied the ring and put it back together again carefully. However, didn’t do a continuity check on the wiring, which I must do.
Out of interest, would it also cause the drum to fast-spin backwards like I described above, and an eventual ‘lock-out’ with the machine, and not doing the things it should when on a particular setting?
Another thing I noticed is that on the PCB there is a large, long resistor raised well above board level, and it’s been getting hot as can be seen by discolouration to the adjacent timer plastic. There is no visible value on it but was reading something like 50K I think. It gets too hot to touch when the machine is on.
My concern was that the forwards then backwards spin, coupled with the locking out and not doing as it should on the settings might have meant that the IC is faulty (NEC 452178EUV4)…
Re: Bluesky BLF1011SP – drum stuck on fast spin
Nope, still sounds like a tacho related fault. Resistor does get very hot.
Isolate the two wires from the motor plug to the tacho and trace them up to the PCB. Give them a gentle tug at the motor plug end, often the wiring breaks inside the insulation so it appears OK until you pull it.
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