FIXED 2018 GDF620HMJ6ES GE Dishwasher: No display on control panel

[Islandvic]

Model Number

GDF620HMJ6ES

Brand

GE

Age

1-5 years

First post here on the forum.. looks like @Jake has helped many members on the forum with their dishwasher problems.

Appliance: 2018 GE GDF620HMJ6ES Dishwasher

Problem: No display on control panel, green LED blinks rapidly and continuously on main control board (rectangle style, not the trapezoid shaped board)

History: Probably twice in the past year the dishwasher would not turn on after circuit breaker tripped and was reset. Breaker had to be cycled off/on again for dishwasher to turn on. Now the dishwasher has no display. Previously the dishwasher would turn on when breaker was flipped back on. (older home and one circuit breaker powers the fridge, countertop outlets and dishwasher... so if trips a couple times a year). Dishwasher works perfectly fine otherwise and I prefer to repair it versus buying a new one.

Troubleshooting:
I have checked the following:

- There is 110v to the wiring harness and to the main control board when plugged into the harness

- green LED blinks rapidly and continuously on main control board

- LED continues to blink rapidly when the other wiring harnesses are unplugged

- I have disconnected power to DW rest for over 5-10 min numerous times, with and without the wiring harnesses plugged into the main board. Still nothing on the UI control panel.

- There is 13.5v from control board to the UI board (black/green & yellow/blue wires). I checked at the main control board and at the end of the wiring harness that connects to UI board

- Disconnected wiring harness between main board and UI board and checked continuity with ohm meter at each wire at both ends of harness. Each wire appears to have good continuity between the connectors.

- I can not enter service/diagnostic mode after holding down the Select Cycle and Start buttons.

- The service document that's folded up and tucked under the dishwasher says a steady blinking LED indicates "Software Error, replace MC".

Questions:
- What else can I do to further diagnose the problem?

- Should I replace the main control board, the UI board? I'm leading toward replacing the UI Board, but the the service document indicates the replacement of the main control board.

- If I replace the UI Board, is p/n WD21X31902 the updated part?

- If I can repair the dishwasher, what can I do to help prevent the issue from reoccurring in the future? From my research it appears it's very common for GE dishwashers to have main control board and UI board failures.



I plan on ordering the part today if I can get some help from the forum to confirm which part I need.

For anyone who can offer their experience and expertise in the matter, I appreciate your assistance.

Thanks

 

[dashriprok]

I replace lots of electronic control boards on ALL brands of dishwashers. From what your symptoms are, yes you need a new main electronic control board on your GE dishwasher. Occasionally, I do get a unit where I have to also replace the UI board but it's not common to replace both.

 

[Islandvic]

Thank you @dashriprok

What makes you lean toward main board replacement?

Asking because the UI board is getting power, but doesn't light up.

 

[dashriprok]

The light on the main board should not be rapidly flickering. Unfortunately, diagnosing modern appliances is not an exact science and the service manuals are skimpy on diagnostic information. Be sure you can return the main electronic control board if that doesn't solve your problem. Also, changing the main board is easy but changing the user interface board is trickier so that's another reason to try the main board first.

 

[Islandvic]

Yesterday I pulled off the door and took it apart to get to the wiring harness and to visually inspect the UI board. So I have easy access to both boards now.

Yeah I will have to check the return policy of where I get the part from, I figured most places do not accept returns on electronic parts.

 

[Jake]

The light on the main board should not be rapidly flickering.

On this model with the square board that is normal.

So on the square board the flashing light means that machine control board is working and the problem would be the UI Board. Here's the UI Board for your model: WD21X31902

Here's another person with this same issue and the new UI Board fixed it:

FIXED - GE dishwasher GDF620HMJ6ES Stopped working, no display, status steady blinking green

Hi all. Jake, you’re a dishwasher miracle worker! My dish washer stopped working all of a sudden. Ran a load, dishes dirty, tried rubbing another to no avail. I did notice it looked like a plastic drinking straw fell down and had melted some/got cut. I checked breaker, not tripped. Turned on...

www.applianceblog.com

 

[Islandvic]

Thank you @Jake

Ordered the part a few minutes ago and will report back how the repair goes when I receive the new UI board.

I'll be using this forum for my appliance fixes and troubleshooting from now on.

Happy Holidays !

 

[Jake]

Ok, sounds good, let us know how it goes.

Happy Holidays!

 

[Rosy Baldwin]

Thank you @Jake

Ordered the part a few minutes ago and will report back how the repair goes when I receive the new UI board.

I'll be using this forum for my appliance fixes and troubleshooting from now on.

Happy Holidays !

Any updates on this islandvic? I am still awaiting on a WD21X26186 MACHINE CONTROL REPLACEMENT KIT but every place I order from sends me only the main control and it's the wrong PART WD21X32165 instead! I already replaced my UI last summer and the dishwasher still sits, dark and silent.
Crazy and frustrating!! About to give up and try to save for new dishwasher.

 

[Islandvic]

I ordered the "Configured UI Board p/n WD21X31902" that @Jake suggested and installed it. The dishwasher now works again.

While I had the door panel all taken apart, I took some time to thoroughly clean everything.

For some reason the main control board still has a rapidly blinking green LED. Very strange.... We have run multiple loads and everything works fine, so I am not sure why it still has the blinking LED.

Thanks for the help !

​

 

[Rosy Baldwin]

So happy for you!

I suspect my replacement UI board last summer was bad, even though it was supposedly brand new. If and when I can get the WD21X26186 MACHINE CONTROL REPLACEMENT KIT, it's supposed to come with both boards, so I will get a second chance at installing a different UI.

 

[Jake]

I ordered the "Configured UI Board p/n WD21X31902" that @Jake suggested and installed it. The dishwasher now works again.

While I had the door panel all taken apart, I took some time to thoroughly clean everything.

For some reason the main control board still has a rapidly blinking green LED. Very strange.... We have run multiple loads and everything works fine, so I am not sure why it still has the blinking LED.

Thanks for the help !

​

Excellent, glad to hear the new UI Board fixed it.

 

[Jake]

So happy for you!

I suspect my replacement UI board last summer was bad, even though it was supposedly brand new. If and when I can get the WD21X26186 MACHINE CONTROL REPLACEMENT KIT, it's supposed to come with both boards, so I will get a second chance at installing a different UI.

Hi Rosy, I posted another reply in your thread for you here:

GDF630PGM0WW and Machine Control Replacement Kit WD21X26186

Hi. Glad to be on the forum. :)My GDF630PGM0WW dishwasher has been acting wonky for a couple years now. It cleans well WHEN it decides to come on. After going through the circuit breaker reset routine countless times, it would start and run well for a week or two. But since last summer it is...

www.applianceblog.com

 

[Rosy Baldwin]

Thanks Jake!

I am on the verge of giving up on ever receiving the correct Machine Control Replacement Kit WD21X26186. They just keep sending me the wrong WD21x32165 part instead. I had very much wanted to try installing BOTH UI and Main Control that are supposed to be included in that kit but it's hopeless. *sigh. I guess I will have to try once again with the Configured Ui Board WD21X31908, which means disassembling the door, etc.

Do you think it's worth it for me to buy a new door harness too? They don't cost too much and seem fairly easy to install.

 

[Jake]

I guess I will have to try once again with the Configured Ui Board WD21X31908, which means disassembling the door, etc.

You'd have to dissemble the door anyways even with that kit that comes with both boards, you see what I mean? UI Board is always the board at the top of the dishwasher door. Machine control board is always underneath the dishwasher.

Yes, I'd check the door wire harness too.

Check for a loose connection in the electrical connector pins, one or two maybe not making good contact where it plugs into either of the two boards.

Here's the door wire harness for your model: WD21X10545

 

[Rosy Baldwin]

I thank you, Sir Jake! You rock.

Will let folks know how it goes....fingers crossed.

 

[Jake]

Sounds good Rosy, yes keep us posted.