FIXED Samsung Range NE58K9430SS/AA - Oven Dead display/controls

[James Goodman]

Model Number

NE58K9430SS/AA

Brand

Samsung

Age

1-5 years

I have a Samsung Oven/stove (model NE58K9430SS/AA) and my front display/controls no longer work which means
I cannot run the oven at all. The rotary stovetop controls all work.
The problem started after I suspect a power outage occurred during a period when I was out of town .
When I returned to my residence the stove had the normal time-of-day displayed but the time frozen and the touch controls
were unresponsive. After some research I decided to cycle power at the basement circuit breaker feeding power to the unit.
This resulted in the unit's front display going completely dead and unresponsive (though the stovetop continues to work fine)
I have purchased some documentation online for the model but is quite vague when describing the troubleshooting
as it doesn't call out specific pins within a given connector for tracing power to the display/touch controls. I need help understanding how to probe devices on the PCB when the only access seems to be from the PCB backside?
For instance I'd like to confirm I have 12V and 5V power and that these power feeds are going to the front panel.
The transformers that I suspect create these DC voltages are apparent
on the main PCB board at the backside of the oven.I don't see any way to probe the contacts for those transformers other
than removing the main PCB board and trying from the backside of that board. To do this probing I would also have to disconnect all connections so I ouldn't then actually; measure their output. Plus I'd be worried about the 220V floating around on the board if I were to add the connections back.
I still don't know which soldered contact is the input-side of the transformer v.s. the output-side. Other than seeing a '+' and '-' marked on the trace side.
I imagine I could also check for continuity on each side of the respective transformers. Unlike a chip which has a pin 1 designation , is their a way to determine
what pins/contacts are what on these transformers? I've attached a photo of the transformers and the back-side of the main PCB onto which they re mounted. I've tried gogling the info silkscreen onto the part but no matches came up.

 

[rickgburton]

Looking at a similar model wiring diagram, communication voltage is CN201 pin 7=12V 8=GND 9=5V

 

[James Goodman]

Thanks so much for the help and response. I felt looking at the main pcb was too difficult so i decided to look at the other and of the cable running from the main PCB up to the sub-pcb at the front of the stove. On the sub-pcb I found CN200 identified as the connector called out as the ‘COMM’ connector. The documentation said pin 10 was ground so i used my DVM to measure the other pins on the Connector. I found pin 1 @ 4.9v , pins 2,3,6 and 8 @ 0v , pin 4 @ 2.1v , pin 5 @ 2.4v , pin 7 @ 4.9v , and pin 9 @ 12.9 v.
I’d like to think rhis means the voltages are at least reasonable coming from the main PCB. I should also add two other pieces of info: voltage at the rotary controls all measure 244 volts between L1 and L2. This tells me the line power is reasonable. Secondly i do hear a relay click when plugging the appliance into the 220v receptacle. Don’t know what that might be or wether it is good or bad.
So I then tried to check the CN220 (LED) connector on the sub-pcb board and found only pin 2 to have a voltage (4.9) whereas all the other pins 3 through 10 were zero volts . I used pin 1 during those voltage checks as the reference pin
The touchfilm connector had no voltages on any pins but that may have been my issue trying to establish which pin to use as a reference. The normal black triangle i see silk screened on the board for that connector doesn’t have the triangle well aligned to any pin on that connector.
Any suggestions on what to replace or how to proceed ?

 

[rickgburton]

Connectors and voltages don't match up with the one I'm looking at, Post a copy of your wiring diagram here. From what I gleaned from your description this is the part you need:

Samsung DE94-03610A Assy Pcb EEPROM;EEP_01,DE92-03959A,NE900 (AP6244729) - AppliancePartsPros.com

ASSY PCB EEPROM;EEP_01,DE92-03959A,NE900 DE94-03610A / AP6244729 made by Samsung

click.linksynergy.com

 

[bigbuck]

Here is the Fast Track.

 

[rickgburton]

Thanks bb

 

[James Goodman]

Thanks very much for the fast track .pdf, it contains the connector/pin info I need to make better decisions. The service manual I bought online is similar but what I bought lacks the details about the 5v and 12V power on various connectors that the fastTrack pdf has. Much appreciated. I see from the fast track how I can now measure on the Main PCB board.
I am so dissapointed in samsung's troubleshooting guidance, for instance they mention checking voltage regulators on the Main PCB and give IC numbers (and perhaps a chip number in parentheses) but I looked on the Main PCB board ( both sides) and could not find the part they call out. The only IC was IC110 (but no IC02 or IC03 as the document calls out). Virtually all the troublshooting mentions connectors that don't exist in the product. The fasttrack is definitely the appropriate ocument despite the lame troubleshooting text becuase the wiring diagram is exactly the same as I found insid the appliance when I removed the back cover.
I feel sorry for any tech who has to service a Samsung product...and bad for myself that I own this oven, as well as a samsung microewave and refrigerator. They came with the house my wife and I bought so we're stuck with them. The house is in the boondocks so repair places also charge for travel time as well (which is a legit charge) but it makes getting things fixed professionally hard to afford. You guys on this site ROCK!

 

[rickgburton]

The consensus among service techs is LG and Samsung are the two worst manufacturers of appliances ever. They should have stuck with TV's monitors and phones. It's that reputation they use to sell appliances. So you got it figured yet?

 

[James Goodman]

Not yet - these appliances are at a small (retirement) cottage on a Lake that we bought out of state so I have to return there to make anymore measurements. I think I may go ahead and buy the subpCB board regardless so I have something to install once I return there. It is almost $150 so I had wanted a decent probability it fixed something and I wasn't throwing money away.

 

[James Goodman]

So I do have some measurements already in hand to perhaps help make an informed decision on what part to replace first. I measured 4.9 v between pin 1 and 2 on CN200 (LED). Pin 2 is identified by fast track as a 5V pin. Would it be fair to think that means 5V power is being fed to the LED (display) and if so wouldn't I expect to at least see some thing other than a totally dark screen at the front of the stove? It went dark only after I power cycled the stove which with the 5V power still present after the power cycle, seems to contrary to my expectations. LED are usually pretty reliable but even with power it's dark. I am tempted to think the LED part may be failing but even that might be traceable back to the data lines on that same connector. Perhaps they are set to a state that doesn't tell the LED to display anything?
In addition the CN200 (main comm) connector has the 5V power on pins 7 as expected per the fasttrack pdf and as well has the 12V power present on pin 9. Clearly the sub-PCB board is getting the power from the main PCB at the back of the stove. That's leads me to believe the main PCB is less likely a problem but the sub-PCB has died since it is getting power but not making beeps when the touchfilm is touched. Of course the lack of beeps might be the result of a dead touchfilm. CN701 (the touchfilm connector) wasn't probe by me correctly because I couldn't identify the ground pin but now the fastrack pdf makes it clear what to probe. So perhaps I should wait until I probe the touchfilm connector before purchasing a particular replacement part, agreed?There is a mention in the troubleshooting text to confirm a relay on the sub-pcb is operating correctly but I'll be darned if I can find a relay on the sub-pcb (probably more inapproriate troubleshooting text!).

 

[rickgburton]

pin 7 @ 4.9v , and pin 9 @ 12.9 v.

That's the correct voltage from the main board so that's comm voltage. If the LED board was bad only part of the board would be working. Check if it's getting 5V or 12V from the sub board.

 

[James Goodman]

5V is present on the LED connector of the sub-pcb board (CN220). at pin 2 I've attached a picture of the other end of the very short (maybe 4") cable that runs from the subPCB (CN220) to the LED board. You can see it isn't obvious how to probe it. I may have to remove it to probe it or remove the cable and try and probe the cable itself.. I've tried to avoid probing connectors themselves for fear of distorting the connector female connector but I guess it wouldn'be hurt to push a 20 or 22 gauge wire in there?
What does "If the LED board was bad only part of the board would be working" mean? which board are you refering to a 'only part of the board", the sub-pcb or the LED board?

 

[rickgburton]

push a 20 or 22 gauge wire in there?

or a safety pin:

 

[James Goodman]

I finally fixed the problem this week by replacing the sub-pcb board in post #4 (control board at front of oven). Before doing so I measured the remaining voltages using the fast-track pdf provided by 'bigbuck'. It re-confirmed all the voltages that were supposed to be present were except for those going to the display board. The missing display board voltage might have been just a problem with me probing the board as I continued to probe through the conformal coating. That seemed to work on all of the other connectors but I'll admit even when I probed the new board (after I hooked it up) I couldn't reliably get the display board voltage (though I did once or twice get the proper reading).I would have piursued that issue with rickgburtons suggestion but since I had a new board I decided to proceed regardless.
So in the end it was the control board at the front of the oven as 'rickgburton' had presented in a photo earlier in this thread in post #4.
I'll also add that when I started shopping around online for the board I found a comment by another person who had purchased the said board and they described the identical failure - even with the same cause - a power outage.

Lastly, not more than a couple hours after I installed the board and my wife and I enjoyed an oven heated dinner what should happen - another power bounce from the power company.
I need to get a whole house surge protector installed ASAP...
Thanks to both of you for the great advice you both provided and the fast-track document.

 

[rickgburton]

Glad we could help!