Bosch Dishwasher Takes Forever to Complete a Cycle

I have actually been on a service call where the customer had hired another servicer to repair this problem. The other servicer, obviously merely a parts-changing monkey and not a real technician, simply slapped in a new heating element, didn’t bother to check his work, collected his money, and left. I asked the customer why she didn’t call him back to repair the problem for which she had hired him in the first place. She said he was too hard to reach, has left several messages with no return call, and she’s rightfully concluded that he is simply an incompetent cockroach and she wanted to try someone else.

Now, in the Bosch dishwasher, one indication that there’s a problem with the water heating circuit is if the dishwasher takes forever to complete a cycle. Note that “problem with the water heating circuit” does not equal “bad heating element.” While it’s true that the heating element is part of the water heating circuit, it is only one of several parts which can fail and kill power to the heating element. “How can we tell this?” you ask, incredulously. Well, Slick, a real technician uses a multimeter to make some simple electrical measurements so that he can determine, with absolute certainty, which part is bad. No guess work involved here. No replacing a part and hope you get lucky. Real technicians do something called “troubleshooting” in order to prove which part is defective.

So I pulled the wiring diagram for the dishwasher and measured the continuity of the heater and the heater’s thermal cutout fuse– both were good. Therefore, I knew that the problem had to be in the control board. So I opened the control panel, pulled the control board out and, walla!, found a burnt solder joint at the heater relay. How ’bout them apples?

Bosch Dishwasher Control Board with Burnt Heater Relay Solder Joint

So I got my solder gun from the van, soldered the connection, popped the board back in and ran the dishwasher. Within minutes, that heating element was drawing 11 amps, right on the design specification for that unit. Another successful Samurai repair.

If your control board is beyond repair or failed in another manner, you can buy a replacement control board here.


 

22 thoughts on “Bosch Dishwasher Takes Forever to Complete a Cycle

  1. Jazzer

    Thanks for your info on the bad soldier joint for Bosch dishwasher. Sure enough, I opened up the front and just as pictured. There must be a little too much amperage for this connection as I have seen other posts (not as detailed as yours, thank you!) that had the same description.

    I have repaired the connection, and testing right now.

    Thanks. Jazzer

  2. MrMark

    When you come across this problem, the repair is generally not as simple as reflowing the solder at the joint.

    I first went down the path of reflowing the solder joint on my personal dishwasher. That lasted about a month before failure again. Digging deeper, I found that the relay contacts are only rated for 10 Amps. Bosch themselves say the heater can be checked by measuring 11 amps on the wires leading from the relay to heater (or by measuring the DW current at the wall.).

    Best solution is to replace the relay with a 12 amp rated version, which is what I did over a year ago. I have since repaired 2 additional boards, each having the same problem.
    After dis-assembly of the relays, I found where the contacts were heavily oxidized, and the reeds holding the moving contact, plus the reed holding the fixed contact, were heat tarnished, proving that reflowing the solder may buy you some time, but there will be eventual failure.

    Yours can be repaired at nominal cost. Contact me at BoschRepair at tx.rr.com for more information.

    1. pferry

      Great information. Two things regarding this Bosch DW repair: 1) For soldering novices, would you please provide some advice about materials and procedure for re-soldering a board like this and 2) If I do need to replace a control relay with a 12 amp, are these relays readily available at home supply stores, and how do you replace them? Thanks a ton. PF

      1. Samurai Appliance Repair Man

        For soldering help, see my post on working with electronic circuit boards:

        http://fixitnow.com/wp/2007/12/03/working-with-electronic-circuit-boards-in-appliance-repair/

        As for the relay, you can replace it if you like but there’s no need to. Simply re-soldering the burnt connection will fix it… assuming that was the problem to begin with. Even Bosch says this in their technical bulletins. I’ve repaired many this way and they’ve been running reliably.

  3. morganhj

    After reading your article on repairing the Bosch dishwasher, I decided to open mine up to see if I had the same problem. Sure enough I saw the burned out solder right away. I went on and solder the spot, put everything back together and ran it through the cycle. When the cycle was over I opened the door I could see the steam from the heated dishes, something that we haven’t seen in a couple of weeks. This saved me a service call and a chunk of change. Thanks again…

  4. amatuerfixit

    You are awesome and I want to send you $10 on paypal for taking the time to write this excellent overview. Do you know how much money you are saving us.. !? I haven’t soldered since my old EE classes. Given the burn, I would certainly expect a poor design here somewhere, hence the thread on 12 amp. On my Bosch SHE44C05 there is a “Power Scrub” that draws more than 10 amp on the heat cycle as the element is advertised to heat water 12 degrees hotter than the normal cycle. I’ve had this dishwasher for 3 years with no problem, but just recently started using the power scrub option. Anyway, please shoot me a note in response and I would like to send a christmas present.. very very nice of you to help us all out.

  5. mac

    I ran into this problem with an shu43 model as well, used the great info on the site to figure out that the heater was not operating. Pulled the control module and found a big scorch mark on the relay pin and board. The pin on the relay had burned down below the surface of the board making a repair somewhat dicey.

    So here’s the good part… Called Bosch here in Canada and they told me that the unit was covered under a safety recall and would be replaced at no charge. I called a local appliance dealer that Bosch refered me to and three days later they came and replaced the module free of charge.

    I believe this is a north american recall. If you get this issue, give Bosch a call to find out if your unit is covered.

  6. ollyochs

    Can anyone advise if this is the same issue for Bosch Dishwasher SGV53E03GB/46, as I also have a heater that will not heat , but is in good order. ie continuity across the terminals.25 ohms.

    the unit is an integrated unit ie the the panel is in the top inside of the door – any one know how to get the the control module that controls the heater?

    Thanks

  7. Paul

    Thanks a lot for the advice you gave on the circuit board burning, it just saved me $300 – $400 in service call out, labour and parts. your ace. I can’t thank you enough as I’m on very low wages and live from pay week to pay week and could not afford to get it repaired. I’ve been filling the dishwasher up with hot water and timing the cycle manually then pushing the 65 and second 55 degree buttons together to empty it, then i would repeat it all again for the rinse cycle. My wife and I have been doing that for about 8 months . Now it works great again and my wife was soooo! happy to see it run like it use to again.
    THANKS SO MUCH. Paul

  8. JonathanNYC

    I tried for almost 2 hours to get the plastic housing off the Control Panel… to no avail. I ordered a new one and I hope it works! my dishwasher was the she44c05UC

  9. applemang3

    First I called Bosch. They told me I needed a new circuit board for $127.30. Next I looked up my buddy Samurai Appliance Repair Man. 30 minutes and $.05 later, my dishwasher is running fine.
    THANK YOU!!

  10. rserbs

    My dishwasher displays 2h when I turn it on and therfore I suspected the heater relay. I got access to the control board and saw thet one of the pins from the heater relay had no solder. So I resoldered this pin and I still see the 2h. Also I made sure that the water enterring the dishwasher was hot.

    The control module is a 266746 and the dishwasher is a SHU531UC/12

    Test 1 displays a 21
    Test 2 displays 0 (indicating all is ok)

    What should be my next move?

  11. rgrizz

    Wow! You truly are an amazing individual for sharing this info. I’ve been washing dishes by hand for the last 4 days since my Siemens dishwasher started taking 3+ hours to complete a cycle and not sanitizing the dishes. Stumbled across your site yesterday, disassembled the dishwasher today and saw the same burnt out circuit board. 10 minutes later I had the thing back up and running PERFECTLY!!!! You just saved me a few hundred!!!!!! Happy Holidays!

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