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Hi all,
I set the Bosch Logixx 8 WAS28461GB off the other night on a delayed start and awoke to find it was displaying E57. The wash appeared to have stopped halfway through, as the load was still dipping wet and the water coming out was somewhat dirty / soapy, suggesting it hadn’t got as far as a rinse. The door was also locked.
After doing some Googling, I tried the old power off for 30 mins but this did not yield any result.
After powering off a few times, I tried several programs, eg wash, spin, drain but they all resulted in E57. The closes I got to any form of success was with the drain program, which counted down from 15 minutes, stayed at 2 mins remaining for around 10 mins, stayed at 1 min remaining for another 10 mins, then went back up to 4 mins remaining before finally resulting in E57. Non of the other programs really get started, they go straight to E57.
There was some suggested it could be an issue with the door locking mechanism. I note that when I start a new program, it does engage the door lock and I hear the solenoid click. After the E57 there is no attempt to unlock the door and I have to pull the little red tab.
There was some suggestions that it could be the motor control PCB. I have extracted the aforementioned PCB and it looks to be in excellent condition, with no signs of burning, bulging capacitors, water damage, overwork, PTSD, etc. I removed the connector and the too appear to be in good nick.
I was wondering if anyone had any tips for how to troubleshoot this further. In particular it would be helpful if someone had the service manual. Coming from an electronics background, I’d be particularly keen to see the pin outs for the PCBs.
Thanks in advance,
MCheck the inverter motor`s field coil first but I reckon it is the motor pcb (the board between the two suspension legs) – had that before a fair few times – but they certainly don`t all fail with the large capacitor visually failing i.e. had them look spotlessly brand new but still a duff board. Had a scoot around to try to suss out E57 (which is not a fault code listed on the Bosch site and one I myself have never seen) and got several differing pointers to do with the door lock which I think is wrong. I found this on youtube.
Ремонт модуля инвертора двигателя
https://youtu.be/_Kx6bJ7_0sw?si=oTKZUG27j3vWtrfvIn English: motor inverter module repair. But only to show the work involved unless you can understand Russian? (which is at least easier than Finnish or Polish!).
Here`s another video this time in German: https://youtu.be/6fQEJ6Qyof8?si=65M6351d6khrMeDPPart number of a complete new pcb is 00706019 price: a finger burning £178.64 though you buy at your risk if that doesn`t cure the problem.
Someone else on this forum might well say the same or indeed something else since you only just posted your post.
As far as a service manual goes I doubt it.Thanks for the info. I had the door lock out and it’s a bit of a pain, as it’s enclosed. I opened it up and released the ping-f***it. It’s as I expected, a solenoid to operate the lock and a sense switch to detect that the lock has indeed engaged. There appears to be some mechanical magic that ensures that it cycles between lock and unlock each time the solenoid is energised.
That perhaps takes us back to the inverter board. I’m slightly uncomfortable at forking out, as previously stated “a finger burning £178.64” when one can’t be sure it’s the board that is at fault. Any tips for testing the board? I see there are three ports on it, power in, UVW out (suggesting it’s a 3-phase Delta wired motor?) and D-Bus. I’m surmising that the D-bus is unidirectional and just tells the inverter board what speed to spin the motor at? Presumably there’s a rotatory counter on the motor that signals back to the main PCB that the motor is indeed rotating? I’m thinking of sticking a multimeter across UVW and seeing if there’s actually a PD across the pins. Also thinking of sticking a scope on the D-bus and seeing if there is any signaling. Is the D-Bus protocol actually documented anywhere?
You did also mention checking the motor field coil. Please could you advise how that is done?
Any other tips would be gratefully received.
Thanks for your reply.
As an update, I measured the PD on the output pins of the motor PCB and got precisely jack. I also put the ‘scope on the D-bus pins and could see a digital signal present until the E57 appeared. Which leads me to suspect that the board is toast.
Got no tips for actually testing the board sadly. It is a case of changing it and hope you do not throw your spons away as indeed I had to do when repairing this stuff; luckily I was always successful in fixing the blighters with a new pcb. Someone else might be able to add something to answer your question more fully if you are lucky.
Great, looks as though you fixed the thing. These pcb`s commonly fail after X years and at 178 quid (they`re ridiculously priced – a Bosch hold your head down in shame moment – like to see that happen !) listed part price it is a frighteningly expensive experience and certainly no joke when this happens.
All the best.I investigated the door locking mechanism and the motor control PCB, finding no visible faults. Seeking advice on troubleshooting, especially if anyone has access to the service manual or insights into PCB pinouts.
UKWG wrote: “As an update, I took a punt on a new inverter board and the E57 went away”
So Joseph one presumes the thing is now working as it should and that was his stated update.Indeed, I can confirm that since the last update we’ve been running around one wash per week without incident. The only thing that I have noticed is that since fitting the new board, my clothes have been taking longer to dry, however I suspect this might be due to the changing weather, rather than changing the board. That remains to be confirmed though.
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