Dishwasher turns on for a second then dead...

[blueman]

We have a Gaggenau 915-710 dishwasher which just suddenly stopped working.

Specifically, there is about an inch of water in the bottom of the tub. Whenever the door is closed, the motor (pump?) hums for about a second and in that short time a squirt or two of water is ejected into the drain hose (which I can feel entering the disposer). Then the machine goes dead -- no noise, no action, no lights.

I tried cleaning out the filters (coarse and microfilters) and looking for any caught pieces.

Clearly, there is power to the machine. Also, it does start for a second and pushing and jiggling the door doesn't change the behavior so I don't think it is the door switch.

Also, nothing lights on the front panel (there is usually a 2 digit LED display) but it may just not have enough time to start up.

Any suggestions on what might be going wrong and how to troubleshoot?

Thanks

[blueman]

Last night, I took apart the unit and noticed that there was what appeared to be a burnt and loose solder joint on the control circuit board at one of the leads for what appears to be a relay (or solid state switch); additionally, the plastic leg of the circuit board enclosure that abuts it appeared slightly brown and burnt. The component that I am calling a relay is the tall rectangular 5-pin box located near the center of the control circuit board.

I resoldered the lead, expecting it all to work; however, when I put it back together, I still had the same situation with no lights on the panel and the pump motor turning on for a brief 1/2 second before shutting down completely.

My guess is still that the problem is with the circuit board having ruled out the switch (by testing it) and checking general voltages on the input/output leads. Would you agree with that diagnosis? If not, what else could it be?

If so, is it likely to be a single component that I can replace or am I going to need a circuit board?

[mm]

It's often the case with various items that repairing one problem doesn't solve things, even though it is reasonable to expect that there is only one problem. One is left to surmise whether it is a coincidence or some other first problem caused this second problem**, or vice versa.

**Then you have to wonder how much you can test the item before you cause the same problem again that you just fixed.

You should be able to find out from Gag me with a spoon, or here, if this brand, or any brand, has a circuit to stop the pump when pumping isn't successful.

In my one experience with draining a dishwasher, with a Sears Kenmore, the anti-siphon air gap, on the sink next to the faucet was clogged with a tiny chicken bone, the one that parallels the drumstick. I had spent a couple hours testing, but diodn't think to check this. 90 seconds to get the cover off, and 4 seconds to remove the bone.

My model tried to pump indefintely, and did not turn off just because it didn't drain, but yours might be fancy. (not that this episode hurt my dishwasher. It didn't.)

[blueman]

OK -- I fixed the problem. Logic, troubleshooting with a VOM, and conversation here and with the Gaggenau customer service line, isolated the problem as a bad controller board.

Gaggenau customer service was extremely helpful in responding to my emails, emailing and faxing me schematics, and calling me back when they needed to research an answer.

They ended up selling me the board for 1/2 price after I pointed out that there have been several reports (as documented online) of faulty boards and solder connections.

The dishwasher now works like new. As a bonus, by comparing voltages on the old and new boards, I was able to further narrow down the problem to a bad transformer. I hope to get a replacement so that I can keep the old board as a spare!

In any case, I ended up getting it all fixed for $60 (including shipping plus a fair chunk of my time of course :) as compared to the $300 plus travel time that the local dealer wanted.

[hallerb]

Congrats. just for the record transfomer failures are pretty rare, most likely something else failed and fried the transformer