I have a Bosch SHE42L15UC/50 Dishwasher. I am trying to find the diagnostic test instructions and can’t find them for my model anywhere (although posts for other models seem pretty available). The Sanitize Light isn’t lighting up and the washer cycles for a long time. Sounds like either the heating unit or the control module is the issue, but want to confirm before purchasing replacement part.
Any help would be greatly appreciated.
The easiest way to diagnose is to visibly inspect the control module. You can test it in a diagnostic mode but will need a meter to test voltage and will have to access the control anyway. When the control relay fails, it is usually very visible. The control is accessed by removing the screws from around the inner door panel and separating the doors. The damage will be visible from the back of the board and will look similar to the picture below. Let me know what you find. Be sure to unplug the machine before disassembling!
Bosch Heater Relay.jpg (51.0 KB)
Thanks for your reply. It is indeed the heat relay on the control board (although I was hoping to get the diagnostic codes to check overall health of the washer to help determine whether it makes sense to repair or replace–it’s just about 5 years old).
The connection was burnt badly through. To repair, I guess I need to replace either the heat relay or the entire control board. I had seen your post elsewhere and just tried to re-solder the burnt connection, but it may be too far gone (the metal leg doesn’t come through the circuit board anymore so not sure there will be a connection–plus, I’m a newbie at soldering). Which way do you think I should go? Also, if anyone has the diagnostic codes for this model (SHE42L), please post. Thanks again.
You will need to replace the board, available at the link below. As far as the diagnostics, I do not have the manual for that model, sorry.
Thanks. Do you sell just the heat relay? Wouldn’t mind trying to replace just that first (since it’s only a few bucks), before dropping $175 into a 5 year old machine.
No, that is part of the control assembly.
No worries, thanks again. BTW, apparently the solder worked. The sanitizer light is back on. Do you think I still need to replace the control assembly or is it okay to keep using the old relay?
If the solder has bridged the connection, it may be fine. If the solder connection is not good, it will fail again. You could try it and replace the board if it fails again. There is some liability assumption when you repair the board rather than replace it. That is a fairly high current draw circuit, so potential for damage goes up when you repair vs. replace it. As a disclaimer, Bosch never recommends repairing that connection but instead replacing the board.
I’ll keep an eye on it and if it seems to be otherwise in good shape, I’ll probably replace the control panel. In the meantime, I tracked down the diagnosis codes so wanted to post in case others could use (see attached). It was located on the bottom left hand corner of the dishwasher (behind the kick plate). Thanks for all your help!
Bosch SHE42L Diagnostics.pdf (938.8 KB)
Thank you, I appreciate you posting that!
