I have read a ton of posts on this topic, but not quite solved my issue yet, but found some interesting stuff. I thought I'd post on this forum as well and see if someone can help. I hate to throw this oven away if it can be saved.
I have a dead display on my Whirlpool double ovens, model RBD305PRS00. This happened before, and I sent the control board to a repair place and they fixed it up and it's been working for 3 years. So maybe it's not the control board again, or maybe it is, but I'd like to be sure before deciding what to do. When power is on, the display is blank. The only thing that works is the oven light, either by the switch or by opening the doors. If you try to do anything else you get a quick short beep, a long beep, and then 3 short beeps. If you shut off the power, and turn it back on, you get a single beep, and still no display.
I did test the control board transformer too, and I do get 120vac across the two red wires to the transformer, and 25vac back to the board across the two blue wires FROM the transformer. Testing the windings per the spec sheet in the over, it seemed a bit out of spec at 57 ohms across the primary (spec is 75-95) and 2.2 ohms across the secondary. I found one for $80 new, so I just put it in. Pretty much the same results, so I think the original transformer was fine.
At that point, I felt like it had to be the board again. I sent the control board out for repair again. I sent it to a difference company due to timing and backlog, etc. Anyway, they said the board is not repairable, which I thought was odd. They said it tested ok, and had power where it should, but the display "appeared" to be bad, and they could not locate a new one. Appeared didn't sound very confident. Anyway, they charged me a $40 diag fee and sent it back to me. I could send it to another repair service, but given they said it tested ok, I wondered about the problem being something in the oven itself, although unlikely. I did locate a display on eBay for $140 if I wanted it, but seems like not an easy swap.
After reading all the threads, I thought I'd try a few more things. I cleaned the ribbon cable with contact cleaner, tested the capacitors (one was very jumpy, wondering if it's bad), and resistors. All seemed largely ok except for maybe that one cap, but I may have not got a good test. I also checked for cold solder joints and hit some suspect spots. I put it back in and when I turned the power on, I did NOT get the usual beep I get when the display doesn't turn on. Because the display WAS lit and the oven worked fine, for about 20 seconds. Then the display faded to black and I was back where I started, with the short beep, long beep, then 3 short beeps and no life except oven light. Although I did try to turn the oven on and it did turn on with no display lit, and ran for about a minute before it turned itself off. It was warming up like you would expect.
I did check the control board thermal fuse, which tested closed ok, and I tested (at the control panel) the heating main over thermal fuse, and that tested ok as well. Does any of this point to a cause? I'm not convinced the display is bad or the control board can't be repaired.
I did find online, for $30, Whirlpool repair kits which I assume contain new caps, resistors and possibly the transistors for the board if I wanted to do it myself vs sending it out. Worth a shot, but still doing the homework to see if I can solve this myself. I don't think I want to send the board out again for another $150-200. Kills me that for a single board, this large appliance will end up as junk.
Any help, tips, etc. are greatly appreciated. I'm technically capable, fairly decent with electronics and know my way around a multimeter. :) Thanks.
