FIXED PDT750SSF2SS GE Dishwasher not heating water (flood switch replaced)

gps470

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Model
PDT750SSF2SS
Brand
GE
Age
1-5 years
Here you have it : PDT750SSF2SS , less than 5 years, and all of a sudden it was not cleaning properly one day. I figured that the water was not heating. Tried replacing the flood switch to no avail.

I am not very handy with the electric tools, but is checking the resistance and all the fun stuff the only way to confirm/deny the Control Board problem ? GE wants to send a technician for $100 for diagnosis alone. Parts and Labor would be additional, which in my humble opinion is pretty aggressive.

Any pointers/help would be appreciated.

Thanks
G.
 

gps470

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Forgot to mention : No errors in Diagnostic Mode. Checked and confirmed the heating issue in Service Mode as well.
 

Jake

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Hi,

Check the Service LED light on the main control board and tell us how many times its flashing.

Here's the main control board for your model: WD21X24802 Machine Control

Here's the video that shows you how to remove the cover to access the main control board: Main control board access video

Jake
 

Jake

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Ok,

Lets also make sure you didn't get a dud flood switch.

Ohm test the flood switch, this has been a very common part to fail with issues of no water/water not heating, etc.

Check your flood switch resistance with a multimeter set on 20,000 ohms per post #2 here: FIXED: GE GDT580SSF0SS issues - not washing properly - not heating water.

the resistance across pins 3 & 5 on the flood switch should be about 11K ohms at room temp, and 1,300 ohms at 175 degrees.
Yours uses the exact same flood switch:
WD21X10519 Switch Flood Asm


Jake
 

gps470

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On it. The led is flashing once every 3 seconds. I am going to check the existing flood switch which I took out.
 

gps470

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Kind of lost here, sorry. The manual is not making it very clear which pins on the flood switch to check for resistance.
Let me try drawing it here, may be that would work :

1 2 space 3
4 5 6 7

So, there are 7 pins, I marked them for my reference. Which 2 I should measure the resistance against ?
 

gps470

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Alright, I think I got it : It should be number 5 and 6 as per my numbering (pins 3 and 5 as per the manual).
They are reading 4.47K in my older flood switch which I took out. I am going to check the new one as well shortly for the measurement.
 

Jake

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Ok, good.

Now the fun part, here's the tech. data sheet for your model: https://drive.google.com/open?id=1Fefp5_Ibg86DtJhjwzL5kPqGBSicyP1v

Page 88 Heater Diagnostics, look at the flowchart, yours is the hidden heater model.

Hidden Heater Models--->remove connector J703 check resistance 11-15 ohms. YES or NO? If YES--->check thermistor and wiring to flood switch 11k-12k ohm at room temperature, YES or NO? You already ohm tested it so the answer is YES.

YES--->Place dishwasher in service mode, enter heat test, and check for 120 volts at connector J703

Let us know the result.

Jake
 

gps470

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How do I do that while the machine is running ? Should I take out that connector J703 or there are some terminals exposed which I can test with the multimeter ? Sorry I haven't done this before but I am eager to.
 

Jake

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Leave J703 connected, You should be able to get your multimeter probes in J703, if its too narrow then you'd need the smaller multimeter probe adapters, which you can get at any electronics store.

Jake
 

gps470

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It’s 119.1 v in the middle of the heater test which I am assuming is correct. Looks like this means there is loose connector or damaged wire in the harness somewhere ? Any suggestions where I should check next ?
 

Jake

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Ok good, yes you are correct, it then says check the wire harness to make sure its not damaged, if your wire harness is good, then it says to replace the variable speed motor which has the hidden heater in it.

Here's the variable speed motor for your model you can order: WD35X20599 Variable Speed Pump Kit

Jake
 

gps470

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Ok, I got the motor delivered today. I couldn't find any videos to replace this part, but I know I have to remove whole dishwasher out. Any guides on how to proceed after that ?
 

gps470

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Well, it’s didnt go well. Firstly the motor I got was from eBay and was branded new, and it kinda looked like that. I now have an open dishwasher which I couldn’t fit back it properly with torn insulation and still not heating during the heater service test. I guess it’s time to call a pro.
 

Jake

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Ok, ebay is not a reliable place to buy parts, even if they say brand new, ebay doesn't monitor where sellers get their products.

That's why its best to always order appliance parts from an appliance parts store even though the price may be higher, at least you know the part is OEM and legit.:)

When you order parts from AppliancePartsPros and RepairClinic, you have 365 days warranty and 365 days to return the part/parts for a full refund, less shipping, for any reason, even if you install the part/parts and it doesn't fix the problem.:)

Jake
 

gps470

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Messages
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Location
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Ok, ebay is not a reliable place to buy parts, even if they say brand new, ebay doesn't monitor where sellers get their products.

That's why its best to always order appliance parts from an appliance parts store even though the price may be higher, at least you know the part is OEM and legit.:)

When you order parts from AppliancePartsPros and RepairClinic, you have 365 days warranty and 365 days to return the part/parts for a full refund, less shipping, for any reason, even if you install the part/parts and it doesn't fix the problem.:)

Jake
Do you recommend going that route and give one more try with one from appliancepartspros or repairclinic?
 

Jake

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gps470

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It’s getting interesting. I got a brand new motor today and somehow even that has not fixed the issue. I tried running the heater test twice in service mode and the water is still cold. Any clues Jake ?
You have been very helpful so far. I am thinking this is a small issue somewhere but I don’t know what to look at now.
 
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