I have a 30" 800 series, no mention of 'D' error codes in the manual. Have you called Bosch? If you get an answer, could you please post it here? I'd like to make note of it in my manual just in case.

Best of luck getting this resolved!

I second Sandra's advice to call Bosch tech support.

Meanwhile, a couple of random thoughts:

I notice in the manual that the total allowed power to the cooktop can be set, from 1000W to 9000W. Perhaps the limit
on yours is accidentally set to a value less than 9000W. This is accessed in Basic Settings, c7.

Do you have a larger pan/pot? Maybe the pan detection is more picky about size/type of pan when on boost.

I have the 800 series and just ran a test with a pan that covers the outer ring at about 75%. I had no issues.
I would call support and see if they have any ideas.

I wonder if we can have access to a service manual for this unit so we can diagnose the codes ourselves.

Looks like the problem is a "Super Booster Relay" Code d2 (alternating and flashing d and 2).

I seem to have a decent relationship with the repair company for warranty reasons for my appliances, they should have the part in in a week or so.

Looks like the gods of appliances are out to get me... middle hob motherboard was shipped and it was replaced and i get the same error code.

On a side note the inside is very interesting and very easy to take apart and do maintenance on. The downside is everything is very costly with these machines.

Once again middle hob outer ring works but boost fails.

Did you check the settings for maximum power limit?

@attofarad: Yes i checked the settings did a factory reset as well and then rechecked.

You can clearly hear a relay go click... i am thinking if there is a separate power board that is faulty.

Each group has a different board and i did not see a separate board for power but then i did not take group three hobs out to see the boards underneath it.