Thermador display is very dim

I had the usual problem - display dimmed slowly since 2000 (model SCD302). I replaced only the 68uf capacitor, using a 22uf and 47uf pigtailed in parallel (soddering negative and positive leads to each other, cutting one’s leads short and one set of leads left long to insert into the circ board holes). I used 50v 85 degC caps from radio shack (which doesn’t stock 68uf unless you are lucky enough to find one rated 35 or more volts in their grab bag assorted caps bag). I used Radial lead capacitors. I couldn’t find the 105deg rating but will replace again if need be…

Taking the cover off is easy - just undo the 2 phillips screws at the bottom edge of the control panel and lift it up and off - carefully. It will fall down and stress the connectors - so slowly lean it back 90deg and tape/wire in place in a hanging position while you work on the display.

Next undo the 3 screws holding the display and pull it out - then take off the 3 wire harness connectors carefully - using a small flat jewelers screwdriver to help along if necessary. Take the board to the bench. Then carefully pull back the 2 small black plastic tabs holding the circuit board till the board pops over the tabs on both ends - then slide the board free from the larger tabs on the other side. Once the board is out it’s easy to work on. Be careful not to static charge yourself and fry the board. Reassemble in reverse.

oh, and remember to turn off the breaker before you start…

Many thanks to those who posted on here before - this was an easy 5 dollar and 1 hour fix. -tim

Folks - I replaced the three capacitors exactly as described - total cost less than $10, oven is back online, wife is on to other topics - life is better. Thanks to all posters, this string was awesome.

Hi and help please: I have read everything on the entire web and also this site to try a home fix on the dim temperature readout that everyone has had luck doing on the cheap. I have a 12 year old thermador double electric wall oven. My local appliance store now wants $680 to do this. I have the front of the oven off and am trying to remove the board. However, the wire connectors seem to be stuck. I cannot pull them off the board without risking breaking the wires or the board. There are 101 separate wires each with their own connector! and only a few of them come off easily. Each post talks about easily getting the board off so I must be missing something.Any insight into how to loosen the connection?

[quote=viljef;95663]I took just the display out…not the circuitboard that is located behind the plenum. It involves removing the touchpad controller. Then the display itself has 3 screws holding it in place.

I then replaced 3 capacitors…the two 470 uf’s and the 68 uf (all 35 V). They are all grouped together at one end of the board. The originals were rated at 105 deg C. I was able to buy 2 470 uf’s at 125 deg C, but the only 68 uf I could find was still 105 deg C. Th ethinking is that the heat from the ovens causes the capacitors to degrade over time. Watch the polarity when replacing them…the light stripe down the side of the new capacitor should be in the same orientation as the old one.

I bought the components at Mouser Electronics for a grand total of about $4. The shipping was more than the cost of the capacitors.

I am not a proficient solder iron user, but the whole repair took me less than 30 minutes, and the display is as good as new.[/quote]

You are correct about heat causing them to degrade over time. Electrolytics have a rating in hours (typically, 2000 or 5000) at a specified temperature (often 85C, sometimes 105C, sometimes more). You will double the lifetime for every 10 deg. C cooler the part runs. So… buying those 125 deg. parts instead of 105 deg parts probably bought you 4x the lifetime (assuming the rated # of hours was the same). Google for “Arrhenius” if you’re curious.

Henhawk
Can you supply a picture of the board and wires I may be able to help you. There are only three different connectors on the display board.

Okay here is a photo of what it looks like when we took the front off of the oven.
Can’t figure out how board comes off when there are so many wires. ANd they are on real tight. Thank you
photo.jpg (37.1 KB)

So I replaced the caps. Still dim. Thermador sent me a whole display unit to replace many years ago. When the replacement went dim, I was excited to find this solution but I have the 220uf instead of the 68uf. There is a fourth cap on the opposite end of the board. Anyone know if this is worth trying to replace or has Thermador screwed me once again?
Thanks in advance.

[quote=scantrell;335349]So I replaced the caps. Still dim. Thermador sent me a whole display unit to replace many years ago. When the replacement went dim, I was excited to find this solution but I have the 220uf instead of the 68uf. There is a fourth cap on the opposite end of the board. Anyone know if this is worth trying to replace or has Thermador screwed me once again?
Thanks in advance.[/quote]

I just spent a few hours today replacing all the capacitors on my board. There were three. Two uf470 16v and one uf 100 50v. I wonder if the display unit itself is bad. It lights up pretty well in the middle. But the top and the bottom are dim. Does anybody know what that means?

Charlie in Portland.

I replaced my caps - two 470 uF’s and a 220 uF - and the display is still dim. It’s actually slightly brighter in the middle of the clock, but the oven temps are still unreadable.
Any ideas would be GREATLY appreciated!

Unfortunately I found this site too late. Here’s my situation. I have a Thermador SC302T double oven with a display that is out. Based on instructions from another forum, I opened the control panel, removed the display unit and removed the controller board with the 3 Capacitors (2x 470uf 35v and 1 68uf 35v). I cleanly removed the caps with a desolder tool.

I ordered the replacement hi-temp capacitors from Mouser and they should arrive later this week. Everything was going well till I read this site suggesting I needed to install the new capacitors with the correct polarity. Unfortunately I didn’t mark the + when I removed the old capacitors.

So how do I know which is the positive connection on the board when I install the new caps? I can’t find any markings to properly install the new caps. Any help would be greatly appreciated in determining how to orient the caps before I solder them.

@Heatwave: There’s a dark line on the component side of the PC board next to where the caps live. The dark line indicates the negative side of the cap.

Thanks, that is very helpful info.

Does anyone know which caps i need to buy for a SC301ZP single oven?
any help is much appreciated!
Thanks

This is a great thread that saved me $300+ bucks!

The only capacitor that absolutely needs to be changed is the 68uF - (Mouser 667-EEU-FC1V680) one. On my board it actually had a red spot under it which told me that it was burned out or overheated to the point of melting.

I replaced it and the display works great. One thing, be very careful with the ribbon connectors. They are delicate to the extreme. I had to remove and replug them several times since the oven was giving me an error each time I did it.

If anyone needs this repair, I’d be more than willing to help. It took me less than 15 minutes. The fact that repair people would charge you over 200 bucks for this is really a ripoff.

I replaced all the caps on my display board and the display is as bright as it was when new, thanks for all the great info!! sure is simple to do, such a rip off, we were quoted $550 for the repair, took me all of 20 mins and $12 for parts( got enough caps to do it again..)
Thanks again!!

[quote=Doza;575683]This is a great thread that saved me $300+ bucks!

The only capacitor that absolutely needs to be changed is the 68uF - (Mouser 667-EEU-FC1V680) one. On my board it actually had a red spot under it which told me that it was burned out or overheated to the point of melting.

I replaced it and the display works great. One thing, be very careful with the ribbon connectors. They are delicate to the extreme. I had to remove and replug them several times since the oven was giving me an error each time I did it.

If anyone needs this repair, I’d be more than willing to help. It took me less than 15 minutes. The fact that repair people would charge you over 200 bucks for this is really a ripoff.[/quote]

Does anyone have pictures on how to remove the display? I am having a tough time figuring it out. Thanks!

The instructions are attached to the reply.

Gene.
REMOVING THE CONTROL PANEL.pdf (71.4 KB)

[quote=Gene;604795]The instructions are attached to the reply.

Gene.[/quote]

Gene,

Thanks for the instructions on removing the display and relay on my Thermador!

Appreciate you very much.

JoeyP

You are welcome JoeyP. Keep us posted.

Gene.

I ended up buying the full replacement units. Now my display and oven don’t even power on. I may have a bad touch board as some of the connecters (4 prongs) are loose.

I may go the capacitor swap method…picture for reference only (from prior post)