GDT635HSJ2SS GE Dishwasher Continues To Blow Circuit Boards - No Power

[jmiles1960]

Model Number

GDT635HSJ2SS

Brand

GE

Age

1-5 years

I am on the third main circuit for my GDT635HSJ2SS GE dishwasher in the past 4 months. The dishwasher loses power, (no lights on the main display), I replace the main circuit board, and it will run for a month or two and the problem repeats. It is not tripping the power circuit breaker and power is fine to the dishwasher. I am lost as to what is causing this or how to diagnose. Fortunately, the dealer has been generous enough to the replace the board for free (once).

Any help or suggestions regarding how to diagnose this would be appreciated. Could the UI board be bad also, causing the main circuit board to fail? I have not yet dropped the main board to look at the LED(s) yet.

Thank you!

 

[Jake]

Hi,

Lets first--->Check the machine control board STATUS LED (its located underneath the front on the dishwasher). Tell us how many times its flashing in a row, or if its STEADY ON or STEADY OFF.

Here's the machine control board(under the dishwasher) for your model: WD21X24900C

To view the STATUS LED, remove the lower access panel of your dishwasher. You DO NOT have remove the control board from its metal casing when you view the STATUS LED.

When you have that panel lowered down turn the breaker back ON to your dishwasher. When viewing it leave all the electrical connectors to it plugged in.

Jake

 

[jmiles1960]

Jake - Thanks very much for the info. I removed the power plug from the main board, dropped the main board as per your instructions, re-inserted the power plug, the dishwasher display powered up! The LED is blinking slow: every 2 - 3 seconds. Strange, when I cycled the power at the circuit breaker, it do not power up, but so far - the panel display is working again. Any advice regarding the problem is greatly appreciated.

Thanks again - Jim

 

[Jake]

Ok Jim,

The problem sounds like your heating element is bad and tripping the CSM and thus that's why it starts working again after you power cycle it.

To verify that, just remove power from the dishwasher, then remove the 2 wires from the heating element(don't let those wires touch anything) and then restore power to the dishwasher and start the dishwasher and see if it trips the CSM again, if NOT then we found the problem is the heater itself.

Here's the heating element for your model you can order if needed:
Heating Element WD05X24776


There is a video in the part link that shows you how to access the heating element.

Jake

 

[jmiles1960]

Hi Jake,

Thanks again for your diagnosis and this info. My dishwasher lost power again after a running a load of dishes. This time the LED is flashing constantly; I would say once per second or so. The control panel is dark on the door as before. I have not removed the power plug from the board to attempt a reset.

If you believe this is caused by the heating element, I will order one and proceed with the repair. I could definitely tell it was drying (heating element producing heat) during the last load I ran. Could the heating element be bad even though it is producing heat?

Again, many thanks for your expertise and help here.

Also - is there somewhere I can buy or obtain a copy of the Service Manual for my dishwasher? (Model: GDT635HSJ2SS).

Take care,

Jim Miles

 

[Jake]

Hi Jim, Yes a faulty heating element can cause the CSM to trip if its drawing too many amps.

Here's the service manual: https://drive.google.com/file/d/1XTOXM0wA0UJEuucW0deIni17sMPtDGtD/view?usp=sharing

Page 39: CSM To Enter Consumer Error Mode

CSM (Current Sense Module) Introduction: A CSM is a protective device that is located on the main control of GE Dishwashers. This device is designed to trip if current leakage to ground is above 20mA ± 5mA if detected. The CSM functions similar to commercially available GFCIs, if tripped the dishwasher will be non responsive.

Check for a water leak underneath the dishwasher, if no leak then reset the CSM and see if everything is back to normal again. The CSM is reset when Service Mode is entered.

To Enter Consumer Error Mode: With the dishwasher in Standby Mode (not running a cycle), press and hold the Cycle Select and Start buttons simultaneously for 5 seconds.

The dishwasher must be in Consumer Error Mode to enter Service Mode. Entering Service Mode will reset the CSM.

To enter Service Mode(While in Consumer Error Mode):
--->Press and hold Cycle Select pad for 5 seconds.

Exit Service Mode by pressing and holding Cycle Select and Start pads for 5 seconds.

Page 41: Machine control board blink pattern--->1x per second--->Communications lost between control boards. Check connections, replace UI or MC as needed.

The UI operational voltage is output from the main control board on connector J722 pin 2 black/green to pin 5 yellow/blue. If 13.5 Volts DC is not found here, then replace the machine control board. If 13.5 Volts DC is found here, then replace the UI Board.

Here's the UI Board for your model: Configured Ui Board WD21X32000

Take the voltage reading from the J722 connector on the back side of the control board.

That J722 connector is on the other side of the control board, look here:

It's the one on the left above the ethernet port.

Let us know what you find.

Jake

 

[jmiles1960]

Jake -

Thanks again for the help and service manual. I have not had a chance to read through it, but here's what I did so far:

1. removed and reconnected the power plug to the main board. The dishwasher again powered up, including the door display panel.

2. the LED is blinking slowly, maybe every second on / off now. (unit in standby mode) Is this normal? Above, I thought you wrote it means a "disconnect" between the main board and UI board, but the dishwasher appears to be working as expected.

3. I was going to run a cycle today with "heated drying turned off" to see if the main board does not trip. As you mentioned, possibly the heating element is drawing too many amps. My thinking is this might confirm if the problem is the heating element. I can find no leaks (water) to the floor anywhere.

Appreciate your help and advice. If it sounds like the heating element, I am glad to do that replacement. I was not sure if the UI board needed replacing, but it seems to working.

I am going to read up on the "Service Modes" in the Service Manual and hope to gain further understanding.

Take care,

Jim

 

[Jake]

Yes Jim, Try No heat, but still the heating element will come on to heat the water in the wash cycle, unless your model has a option of NO HEAT WASH too.

Like I mentioned in post #4--->To verify that, just remove power from the dishwasher, then remove the 2 wires from the heating element(don't let those wires touch anything) and then restore power to the dishwasher and start the dishwasher and see if it trips the CSM again, if NOT then we found the problem is the heater itself.

Jake

 

[jmiles1960]

Jake,

I am sorry to bother you again with this issue. I took your advice and replaced the heating element back in early October. My dishwasher worked fine for over a month. Yesterday, the control panel went dark again, (no power). The main control board LED is Steady ON (green). I tried resetting the power and unplugging the power connector a few times with no luck. I believe the manual says: Lost Control to the UI regarding this issue. Not sure how to proceed from here. Honestly, I have never had this much trouble from a GE appliance. Your advice and diagnosis would be appreciated. At this point, it is likely time for another dishwasher after the man hours and dollars invested in this one.

Happy Thanksgiving! - Jim

 

[Jake]

Happy Thanksgiving Jim!

Did you check the voltage to the UI Board? Usually its a bad UI Board when the machine control board(underneath the dishwasher) STATUS LED is STEADY ON.

The UI operational voltage is output from the main control board on connector J722 pin 2 black/green to pin 5 yellow/blue. If 13.5 Volts DC is not found here, then replace the machine control board. If 13.5 Volts DC is found here, then replace the UI Board.

Here's the UI Board for your model: Configured Ui Board WD21X32000