Bosch SMS40A08GB stops and starts during cycle

[jb72]

Our dishwasher seems to have 2 (connected?) problems –
– it will stop during the cycle – the display flashes suggesting the door is open – the door isn’t open but a gentle push restarts it
– it again will stop completely – lights go out – opening / closing the door does nothing – left for a while the power returns and it continues

Having spent some time searching the second problem is maybe a power problem on the main PCB?

I _think_ the door issue was first. Is it possible the door switch is faulty too? And has in some way affected the power supply?

Any pointers would be appreciated. Thanks.

[subspace]

Sounds like the same problem I was having:

https://www.ukwhitegoods.co.uk/forums/forum/public-support-forums/help-and-support/dishwasher-help-forum/861437-bosch-sms40c02gb-switches-off-and-on-during-a-cycle

[electrofix]

with the door latch check the hinge bearings are not broken or missing

https://www.bosch-home.co.uk/store/00165296

Dave

[jb72]

[USER=”57385″]subspace[/USER] it does sound the same. We’re away now .. I’ll pull the board out when we get back and have a look. [USER=”4209″]electrofix[/USER] do you know if the PCB in ours is similar?

As for the hinge bearings … I’ve no idea what to check there. Does that bit of plastic deteriorate and lower the door slightly? If I push the door in slightly or apply a bit of pressure to the top of the machine the cycle continues.

​​​​​​​Thanks both of you for your responses.

[electrofix]

they are right at the bottom of the door its where the hinge pivots. if they break the door lowers by 2mm or so and can cause problems
your main pcb is at the back rhs

Dave

[jb72]

Ah .. that makes sense, a 2mm drop in the door could do that. Thanks.

Sorry .. is the PCB in the door or at the rear of the machine? … I’m new to this! Is is reasonably easy to get to?

Thanks again.

[subspace]

Pretty sure it’s the same board.

If its the same layout as mine the board is near the bottom right rear corner. You can get to it by removing the side panel. The position of the power socket will tell you where it is.

I also replaced the capacitor circled in red as it was supposed to be 470uF but when I tested it, it had fallen to around 330uF.

[IMG2=JSON]{“data-align”:”none”,”data-size”:”full”,”height”:”460″,”width”:”895″,”src”:”https://i.ibb.co/y8TLJ7z/board.png”}[/IMG2]

[jb72]

I see .. is that the power socket on the right of the board?

[electrofix]

jb72 wrote:I see .. is that the power socket on the right of the board?

correct

Dave

[jb72]

Just to update this.

Finally got round to replacing the IC as suggested. And despite my particularly ham fisted attempt at soldering it worked .. so far I’ve run 3 successful cycles and it’s not missed a beat. So big thanks for the advice!

I think if it needed doing again I’d find someone else to do the soldering .. I’m happy doing basic soldering but removing the IC was tricky and I was lucky not to cause major damage to the board!

I’ll add .. the door bearings looked ok and the machine doesn’t pause as it did, so maybe the problems were linked. We’ll see.

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