THermador POD301J Oven On Indicator DIM

[JP_Austin]

I recently fixed my wonky Thermador POD301 wall over with the analog clock control board. The OVEN ON indicator has been not working lately and the wife is reporting that the unit shuts down from time to time during a cooking session. If she flips it off and back on it will often complete the cook. Not a good way to have a big meal on time!

I'm an old time appliance tech from years past but lately I have been an electrical engineer (30 years). Once the front panel was removed it was apparent the surface mount caps on the control board were not good. See below. 

 

 

The caps were faulty. These were only rated at 6.3V and 330uF but I replaced them with 330uF and 16V caps I had lying around. It worked very well and the oven is back to working well.

[AccApp]

"I'm gonna bust a cap in yo'....Wall oven?" Said no gangsta ever

Nice fix, gotta love how they bulge when they fail. I also like when MOV's release their magical smoke.

[JP_Austin]

Well this one came back to haunt me! Same thing dim to no blue OVEN ON LED while operating. Seems to be running OK but no indicator. Wife tells me it did shutdown a cook about three weeks ago. Every time I use it seems to be fine. Then again I typically only use it for 30 minutes or less. She bakes and can have it tied up for hours.

I tested the LED with a small power source (3V, 15mA limit) and the LED lights up OK. It must be on purpose that the controller is not lighting the LED (some other problem in system) or the driver for the LED is out. I traced it as far as I could but it seems to be limited to the main controller on the board. I am having a hard time believing that the pin drive electronics are weak. The supplies test fine with good voltage and other LED and indicators are clear and bright. I'd kill for a schematic on this thing. Are these available?

A new control board is nearly $300 so not something I want to replace willy-nilly! Do the Thermador's not light the indicator to tell you there is something wrong? BTW  - No error codes have been on the display.

[JP_Austin]

I need to sleep on this one. Assembled it and turned it on and it's working like new. LED is as bright as the day it was installed! Not sure what happened but the LED must be intermittent. I have a 603 SMT blue LED if this one decides to go back out. Only thing I can tell is by energizing  the LED with the external supply it may have made an intermittent LED work again. Just unusual for a potted LED in a plastic case. Yes it can happen but odd.