Dim Clock LCD on Jenn-Air wall oven

[Longbow]

While replacing caps on the display board used to be a great idea, keep in mind that even with a working display pcb, the VFD displays wear out and dim with age. There is nothing you can do other than to replace the VFD tube itself - it is NOT an LCD. Good luck finding just the VFD...that's when you get to consider replacing the entire assembly.

[bluewhale32]

About a year ago my daughters gas range was having the same symptoms as blutos dim or no display so i removed the board and come to find out around the power connectors and various other solder joints had small micro fractures so i just refreshed all the solder joints and plugged it back in and watched it light up good as new cost $0.00 but my time which was well compensated with the smiles that were on my daughters and her husbands face was priceless, not to mention the food cooked on that range is killer.
Thanks Badcaps.net for the fix it inspiration. With the help of this site i have repaired numerous items

[MAYTAG]

I have ordered caps, but I have a question that I haven't seen raised. One of the caps on my board is under the display, which is connected by a couple dozen stiff wires. In order to replace the one cap I would need to bend that assembly about 90 degrees out and then back. Will the leads tolerate that kind of bending? Definitely would rather not de-solder all that. Hopefully it's just C3.

Thanks for this thread; our oven went dim many years ago and we've just lived with it. I'll be tickled if I can get the display lit again!

[Per Hansson]

MAYTAG: If it's not mentioned before in the thread it might be useful to post a picture of that cap, to get rid of any confusion
Also is it possible to read the component designation on the PCB for it without taking out the VFD?

[MAYTAG]

Originally Posted by Per Hansson

MAYTAG: If it's not mentioned before in the thread it might be useful to post a picture of that cap, to get rid of any confusion
Also is it possible to read the component designation on the PCB for it without taking out the VFD?

Alas, i've put the unit back together until the parts arrive. It was one of 4 capacitors, all of which exactly matched the specs in the original post. The designations are visible on the component side. It wasn't C3 but I don't exactly remember which of the others it was. Maybe C7. The VFD covers the middle part of the trace side of the board and I'd have to move it away to get a soldering iron on that capacitor's legs.

The covered cap looks ok. There's a smudge under C3. My approach will be to replace C3 first and see if that fixes it. The other 2 caps next and then deal with the covered one as a last resort. I'll take pics when I next have it apart.

Thanks!

[R_J]

By looking at other pictures there should be no problem releasing the plastic that holds the vfd in place and tilting the display, the flat leads are flexable, just don't start flipping it back and forth.

[MAYTAG]

Well, C3 did the trick. Thanks bluto for the fix, and for researching the replacement part. For nearly 20 years this blank display has been to me like George Bailey's loose bannister knob in Its a Wonderful Life!

[bluto]

Glad to hear the C3 fix worked for you! Per Hansson is going to edit the 1st post of this thread to add a little bit of clarity that has been realized over the almost 9 years that this thread has been going.

[MAYTAG]

And... the result. Thanks again!

[sam_sam_sam]

Originally Posted by MAYTAG

And... the result. Thanks again!

Very nice repair good results

[carlito657]

Hi. I had the problem with my Jenn-air wall oven display being blacked out but the oven still worked. I replaced c3 and the display problem was fixed. One day I was using the oven for about 3hrs and it just shut off and I had to flip the switch at the circuit breaker to get the oven back on. Then after cooking for 30min I had the same problem. I then replaced all the caps on the 2 boards to see if that would solve my problem. I connected everything, turned it back on, and baked for about 45min. It's seemed to have been working fine but when the oven cooled down and the fan shut off, it started beeping nonstop and gave me a f1 error. Any suggestions to what the problem may be?

[Sundancedog]

I was excited to find this forum and post because I’ve been dealing with a Jenn-air wall mount oven with a display that faded out years ago and can’t get myself to pay $170 for a board to fix an oven that is probably not worth that amount. I actually found a deal on eBay about 6 years ago on a used board that fixed the problem but that one faded out after about a year.

I bought the capacitor recommended from this thread from DigiKey to replace the C3 cap. Got the cap and soldered it to the board. I replaced the board and plugged it in and voila, the display works and I began to celebrate and put the stove back together and within about 2 minutes I watched the display dim and vanish 😭.

Any idea about what went wrong with my repair?

[sam_sam_sam]

Can you please post a photo of the controller boards

[redwire]

There might be a cold solder joint on the board for the VFD display tube filaments.
You bumped it changing the cap. Sometimes doing a repair breaks other things.
Either that or your cap replacement did not work out, something went wrong.

[jetadm123]

Sure you didn't install the cap backwards?

[RoadsterZ4]

Thread bump;
Hello all. I need some help. I have a Jennair wall oven. The display has faded to nothing but the oven works fine. I have read on the previous posts about the c3 ECapacitor.

Upon inspection I found the c3 with a resistor soldered in line that is then soldered to the board. the cap is a 220uf 35v; The obvious problem is the resistor has failed and overheated, and popped off the solder from the board (burnt mark also there).
The resistor overheat has made the stripes unreadable.

I am not sure why there is a 220uf in that location. Is this the reason for the resistor to pull it down to 68uf ?!?!
The 220uf doesn't look damaged.
All of the references in this thread say that it is supposed to be a 68uf 35v. Should I just replace it with a 68 and clean up the terminal and install?
I appreciate your help -- trying to get the screen to work before we have family over for Christmas dinners! :o

[sam_sam_sam]

Recommend that you replace the capacitor in question just because it might look okay dose not mean that it is okay replace the resistor and see if the display comes back on if it does not then the display might gone as well these display type as they age they draw more current on the plate heater current and eventually burn out and when this happens it time for a new display or a new controller

[redwire]

There are refurbished/reconditioned Jenn-Air oven control boards out there that have an added series resistor at capacitor C3, in an attempt to make C3 last longer by lowering its ripple current. Like pics here:
https://www.badcaps.net/forum/showpo...&postcount=126
It looks like 11 ohms and 2W.

If that resistor overheated, then C3 has likely failed. Can you test it or look for signs of bulging, leaking etc. It is OK to upsize the part from 68uF to 100uF, I would say 220uF is a bit much but I have not measured the actual circuit.

[RoadsterZ4]

Thanks for the feedback. I have attached some pics.
I ordered a couple of the 68, 220…and the other caps (just in case)

Any idea what size resistor that is? Do I even need to replace the resistor with the 220u?

[redwire]

That resistor is burnt badly, kinda puzzled because it means something else has shorted?
Another post shows red as the first stripe. Newer Jenn-Air oven controller boards use: a 27ohm 3W resistor red-violet-black-gold, and 220uF 35V capacitor. Adding the resistor is supposed to give C3 longer life, as well as the upsizing it from 68uF to 220uF. What happened to your board then?

For a suitable 27R 3W resistor, body is about 15mm long, I'd use flameproof safety types: TE RR03J27RTB, TE ROX3SJ27R, Yageo PNP300JR-73-27R, Panasonic ERG-3SJ270 etc.
For a suitable 27R 2W resistor, body is about 11mm long, I'd use flameproof safety types: TE RR02J27RTB, TE ROX2SJ27R, Yageo RSF200JR-73-27R, Panasonic ERG-2SJ270 etc.

The resistor does not dissipate even 0.5W normally.
I would replace C3 and C4 and test the old parts, one of them should have failed short. That's a bit weird, unless you have high mains voltage or power surges/lightning. I wonder what their operating voltage is. Test diodes D3 and D4 too.

I went down the rabbit hole a little into the circuit. Capacitor C3 feeds C4, so if C3 or C4 fail (low value) it will give a dim display. If either shorts, no display and it would burnt up the resistor.
The board has already been refurb'ed so it will be extra fragile, the PCB pads.