Yeah, my thoughts are a long those lines too. The tranny goes in overheat mode at 101C (214F). And this is naturally sensed by the TCU.
I've adjusted the cooler fan to kick in at 190F measured by the external gauge.
Adjustment is very easy, so I will just have to drive more to get a good feel what's going on.
I took out the boost gauge - so now I have the wide-band and the trans fluid gauges where the ashtray used to be
.
/T