Noticed that the soap dispenser was not working on the Kitchenaid dishwasher (KUDK03CTSS2) in the place we just moved into.

Checked the solenoid and it was definitely burnt out (see pic) and checking the resistance it was next to zero.

Bought a replacement soap dispenser and the resistance on it is 280ohms - in the range it should be (280-340ohms). Put it in but it was still not working.

I put it into the service diagnostic cycle (heat dry>normal>heat dry>normal) and let it run the full cycle but it didn't throw any error codes.

I then ran the service diagnostic cycle again and measured the voltage at the soap dispenser solenoid and it was only getting between 5 and 9 volts so obviously this is the problem.

Checking out the wiring diagram it looks like it's the TR4 triac that controls this circuit. Looking closer at TR4 it looks like part of it has broken off (see pic).

Is this likely the problem and is it possible to solder in a new triac (probably a 50cent item) rather than replacing the whole control board? Anyone know the specs. on this particular triac?

Thanks

Thanks for the quick reply.

Ya, I ended up taking a look at those 2 (TR3 and TR5) and they were both the same (0107NA). Good chance that TR4 was the same (the side with the # on it was blown off). I ordered some Z0107MA TO-92 600V 1A triacs - hopefully a new one of those will work. I assume it won't matter that the ones I'm getting are the MA (600V) instead of the NA (800V) given it's only a 120VAC supply.

Will post back with the results.