SMEG dishwasher unresponsive

[Johnking]

My 10 year old Smeg df614fas has become unresponsive. It looks normal, there are two lights flashing which is the normal status when ready for a new cycle. However the button to select a programme doesn't do anything. The button works electrically - if I hold it while powering on, there is a beep.

This has happened a few times recently, but previously the buttons have worked again after a little rest.

Perhaps not coincidentally, there has been a bad rotten smell inside recently.

Does anyone have any ideas?

 

[Johnking]

Following up myself as I fixed it and it might help someone one day...

I disassembled the machine - removing the rear and sides. Then tipped it onto its door to get at the undergubbins. Discovered the source of the smell - a semi-solid pool of pink decaying sludge covering the bottom tray. Cursed, spent a long time with a roll of toilet paper. Something was clearly leaking dirty water. Soon found the source - what I have now found out to be a diverter valve had a thick crust of nastiness on it. I disconnected it and cleaned it up, and reconnected the hose seals. It may still leak, I could not see anything obvious about the unit itself so perhaps it was the hose seals or the three-o-ring seal where it pushes into the sump. The unit does have a gear that passes to the interior though, so I suspect that to be a source of a slow leak and will recheck after a few cycles.

On the bottom tray there is a flood detection device - basically a switch with polystyrene floats. Some of the pink gunk had got (grown?) under it. Once that was cleaned and all re-assembled, the machine works fine.

Apart from contact with nasty biohazards, I'm very pleased with myself, and sort of think I understand how dishwashers work. I can see I'm going to have to change the air break matrix, it's got a lot of scale build up, but otherwise all looks in remarkably good order for a machine nearly a decade old.

 

[Johnking]

Gurrr.

Spoke to soon. Dishwasher now throws a wobbly with Error E8. Looks like the gunk was the only thing keeping the divert valve working. Nothing physical looks wrong with it, but the microswitch shows high resistance in both positions. I've ordered a replacement switch from RS, fingers crossed.

 

[Johnking]

Replacing that microswitch seems to have fixed it. I think the diverter will still leak slightly from the cog bit, but at least it's running.