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This problem goes way back. This is the most expensive stove that we have ever purchased by far that I bought for my wife. It all started back a few years ago. First the bake element went out. I said no problem, I have had to replace many elements in the last 50 years of owning stoves. I went down to the local parts house & they asked me if I wanted the generic element or the Kenmore element. They said the Kenmore element was about $65.00 (that is by far the most expensive element too). They said the generic was just as good & only $40. I went with generic, installed it, & all went well for about 30 days. Then, suddenly the stove caught on fire. It hade melted the wire going to the element connection & blew the board. We called Sears out. Pardon me, but we were not thrilled with their service. They could not tell us what happened & why. They just wanted to start replacing parts starting with the element (their charge was higher than the parts house even), wiring harness, & board. This is an expensive oven & was only a few years old, but slightly out of warranty at the time & the board alone was nearly $500.00 plus labor. They really had no idea what caused it all though & could not guaranty that it would be repaired. I then found a company that said they could repair the board, make it better than new, plus troubleshoot the root cause for about half. I packed it up & sent it away. I also checked the element, repaired the wires & connections very well, etc. & all seemed well & they repaired the board. We also called a different recommended local repair company out to check everything out before turning it all on again. This guy just ranted about repairing boards being bad & that he could get us a new board for $200 & charged us $100 to repair. However, after he checked everything out & said if it blew now, it was just a bad board, the stove caught on fire & blew again. So, I said let’s move forward & get this new board. He said he would get it ordered & that is basically the last we heard of him. We even told the parts house about him & they said they would talk to him, to no avail. So, we called out another local repair shop, but this time we thought we would try a franchise to see if we could get better luck, actually two of them. They both claimed they could fix anything, but then when we gave them the model number & all, neither one ever showed. So, I contacted the board repair company again who stood by everything they said & offered to check it out & if it could still be rebuilt, do it at no charge, based on what we told them about the sad repairmen. They reiterated that there was a problem with the bake element circuit. They were also able to repair it again. They also said that we should really take care to find another repairman before turning it on again. We also hade the parts house double check the new element & they said “it was highly unlikely that the element caused it”, not impossible, but highly unlikely. They basically did the same thing I did, but with an analog instrument instead of digital (yes, I really like those better too). Unfortunately we have been unable to find a qualified local repairman or lady & there are not that many anyways. Of note, we actually have the oven on, just the large oven bake circuit wires disconnected. The stove top works fine. The small oven works fine, the clock & everything else about the board & display works fine. We are just afraid to turn it back on until someone can identify exactly what it is that is blowing this board. Since we are unable to find a real repair man from Sears to very small & everything in between. I am going to have to do it some how. Can anyone please help? I hope I did not leave anything out.
Hi Dave, if possible can you please provide the details of the company that repaired the oven circuit board.As a matter of fact we have the exact same range and problem! The resistor P3 just went into smoke and burned several component around it. It happened without any warning last weekend I am still thinking what to do next. A new board is almost impossible to find. Thank you very much Angel
Hi @dorry , You would think that for a start the range safety thermostat, part #219 -body diagram would operate and shut down the range before it caught fire, but I am a bit bemused to see it located in (behind?) the small oven rather than the main oven. I would still definitely check that it was OK though. Then there is also the oven temperature sensor (RTD), (part #37 body parts) which should signal (resistance value changes with temperature) the correct oven temperature to the control board and then in conjunction with the oven thermostat (part #12A, backguard diagram) which is used to set the desired temperature, the control board knows when to increase, decrease or turn off the power to the oven element and not just keep it at the same amount or even increase it until a fire occurs and the board also burns out. According to the supplier in the link, the service data sheet is part # 318127039 This will help you to see if it detects a runaway condition or not and then how to check the sensor (RTD sensor) to make sure that it is OK. Hopefully a start. Update (01/08/2021) Hi @dorry , More information to help you. According to the parts supplier I linked the part number for the wiring diagram is 318045338 Scroll down to p.16 to see the oven wiring diagram. I have attached an image of the diagram where it shows how the wires go from the control board to the bake element which I assume is the element that you have currently disconnected to prevent the control board from burning out. Disconnect the wire from the control board and then use an Ohmmeter to check that there is continuity between the wire from end to end (between two green arrows in image) i.e. 0.00 Ohms - short circuit and also that there is no connection i.e. OL - open circuit between the wire and Earth (chassis of oven) when you connect the meter between the wire and the chassis.
(click on image to enlarge for better viewing) The control board must be burning out due to excess current flow. You said that the element harness wire had melted and was replaced. Was it replaced entirely or only back as far as it had melted and a new wire jointed onto it? Also check that the wire gauge to the bake? element is the correct gauge wire for the full length of the wire i.e. check that it is the same gauge at both ends and also compare it to the convection element wire at the control board end as it is the same gauge. The gauge number is next to the wire colour in the diagram i.e. bake element is yellow wire 6 gauge. If the wire is a thinner gauge it would mean that it couldn’t carry as much current as the correct gauge without heating up. A hot wire has more resistance so therefore less voltage is applied to the element (more voltage is lost in the wire itself) so the element may not get hot enough and the temp sensor may register this and tell the control board to apply more and more current etc. This is just a theory of what may be happening of course and may be way off what is actually the problem. There is a wire gauge chart in the wiring diagram but it is not shown in the image I posted so as to keep it easier to view. It is below the wire colour chart- lower right of diagram
If that rebuilt board is catching fire, the company that rebuilt it needs to step up unless…, as mentioned above, the wire is too small. An undersized wire will turn into a heating element and create too much resistance. That can very easily burn out a relay on the board. If were me, I would go buy some over sized wire to replace the wires between the bake element and board relays. That coupled with a new element will isolate the board as the cause if it happens again. Test it with the oven slid out and the back off to monitor. Rob Hill, robsappliancerepair.com
