Thermador range - multiple issues

[RAB_LAC]

New issues with a ten-year-old Pro Harmony natural gas range. I previously had the main circuit board replaced under warranty, discovered an improperly seated wire connector that was causing a thermocouple fault error, replaced a burner on indicator light, and replaced two burner gas lines. Doing this other work on my own gave me confidence that I can fix any issue with the range, as long as I know what the issue is.

I now have two seemingly unrelated issues. First, both Xlo burners are completely dead. No gas, no ignitor spark. All other burners are working. No error code associated with this. Second issue is that the oven shuts off with error code e9 (four blinks of Preheating light followed by three blinks of Heating light), usually after finishing preheating. Oven will come back on if the mode dial is turned off and back on, but it's susceptible to turning back off with the same error. There doesn't seem to be any problem with the cooling fans as the code indicates.

I'm trying to decide whether to tear the stove apart and hunt for causes on my own, or call for service. The warranty service we got was not a good experience. The circuit board replacement didn't fix the issue we called about, and the place refused to return because the warranty had expired (there was a one-week stretch between their service and my call back). I'm not that confident in my ability to properly diagnose the causes, and even though I'm in Southern California, we don't have other Bosch-approved service companies that are willing to come to our place.

Thoughts? Are there steps I could take to diagnose before tearing the range apart?

[16345Ed]

No model number, no help. 

[RAB_LAC]

PRG366EH/07 is the model number

[LI-NY Tech]

Simmer burner issue is likely a faulty simmer controller. The fault code is E43. That’s either a bad cooling fan, a bad hall sensor or a bad sail switch (depending on exactly which set up your oven uses). Both of those repairs can be fairly involved. I’d recommend calling for service. 

[RAB_LAC]

Alright, thanks for the advice.

[RAB_LAC]

Update: I found this tech bulletin (https://f01.justanswer.com/smitty1486/c8b63d31-046e-4870-8c74-fe19eeedf79c_PRG364EDHo7_Error_43_Tech_Bulletin.pdf) regarding the sail switch, and decided to take a look. I found the inspection sticker on the back of the range showing a date of October 2008. According to the tech bulletin, this range probably doesn't have a sail switch. I took off the panel protecting the cooling fan, thoroughly cleaned everything, and double-checked its wire connectors. It's been running at 450 degrees for an hour since reassembly without throwing the error again, which is longer than it's run without the error in almost a year.

Regarding the simmer controller, is that integral to the main controller board (part #00676192)? I watched the technician replace that during the warranty service. The issue that was not solved by the controller board replacement ten years ago was that the ignitors on the XLO burners would click continuously after turning off the burners. We lived with it by fiddling with the knobs until they stopped clicking. The burners stopped working altogether a few months ago.

[RAB_LAC]

Do any service techs here work on Bosch/Thermador appliances without being on Bosch's approved list? I tried a couple places before going with the place Bosch specified for the warranty service, and none of them would work on the range whether it was in or out of warranty. I don't want to waste my time searching for a tech if Bosch really does have service locked down.

[LI-NY Tech]

Just about everyone should be servicing Bosch/Thermador. They are common products, there is no restriction on out of warranty service. 

The simmer controller is different than the main board.