I only work on commercial equipment, so I've never touched a Thermador. Therefore, I can't help you with any diagrams, etc. I can only respond to your final request.
Electronic temperature controls use temperature probes of several varieties - depending on their manufacturer's circuit design. A Type K thermocouple as one example. It's resistance varies with temperature. The control board's signal is a low voltage, so any additional probe circuit resistance, even a crimped connection such as a butt connector NOT designed into the circuit, can alter the probes accuracy to a certain degree (no punn intended). So, any additional resistance in the circuit can affect it's reading - even a weak connection to the control board or the wire harness.
A common cause for failure (and the subsequent error code you experienced) on cooking equipment can be related probe circuit wiring or connections that have deteriorated due to exposure to a hot environment for awhile. Therefore, I always walk through the entire probe circuit to inspect for these symptoms.
You said you replaced the probe, but it still didn't work...and then it did. In that case, if the problem reoccurs and your certain of the probe (and probe circuit's) integrity, your next option would be to replace that board.