8 replies to this topic

[prairiestr]

I have'nt seen one of these before, customer says it will just run and run, never draining unless she selects cancel/ drain.
Suspect temp sensor or heater.
Any hints?

Edited by prairiestr, 08 November 2012 - 04:08 PM.

[Samurai Appliance Repair Man]

Check that model number again: is that SHU or SHV?

Also, the character after the "C" is a 0 (zero) not an "O" (the letter O)

[prairiestr]

Thanks Samurai,
I have'nt seen the machine yet, leaving for call now. I'll get back to you.

[prairiestr]

Model # is SHU43C07UC/22
Ran diagnostic. E1 error code (heating error)
Now for the stooopid questions;
1. Am I supposed to remove the tub from the base tray to work on this thing?
2. If so, how?
Again, this is the first Bosch I've seen.

[Samurai Appliance Repair Man]

This will either be an open heater or NTC (the control for the heater) or a bad control board.

A common problem is a burned solder joint on the control board but not always and this can trick people. If you're not getting the current draw that that Brother jumptrout described, then there will be one of two problems: open in the heater circuit (usually the NTC); or the control is not putting out 120vac to the heater.

It's easiest to check the control.

The control board puts out 120vac to the heater circuit on the red wire. If you're not getting the current draw through the heater, then check to see if the control is putting out 120vac on the red wire. If it is not, then the problem will either be 1) a burnt solder joint on the heater relay or 2) some other non-visible problem with the control board. I have seen the control boards fail in this manner WITHOUT the relay being visibly burnt, so you have to check for voltage the red wire to know what's going on.

The difference between the two type of control board failures is this: burnt solder joints are field repairable but the other types of non-visible failures are not.

And there there is Brother Telefunken's method for checking the heater circuit.

[jumptrout]

The Fermented Grand Master is correct in this diagnosis.
One additional step you can take to verify all heater components are good is; after running the dishwasher for 5 minutes to make sure water is circulating well,use a insulated jumper wire from the incoming power wire on the control board to the adjacent RED wire. Your amp meter over the red wire will read 10.5 amps if the heater components are good. This keeps you from having to remove the dw and then remove panels to access these parts unless they are bad.

[prairiestr]

Thanks for all the help.
Replaced the control board/timer, all is working fine now!
Thanks again.

[jumptrout]

Please tell us the steps you took to determine this repair method so that we might learn from your experience.

[prairiestr]

jumptrout,

I followed your advice and installed jumper wire from power coming in (grey?)  to red heater wire, then used amp probe to look for current,(10amps) this told me other components were functional and the problem must in the control.