SI Drive fault

[Luke Akrigg]

Hi, new member and first post. Just after some information, please excuse the long winded explanation but feel its key to answer my question.

I've just bought a 2011 Hatchback STI a few weeks ago, had no issues until yesterday morning whilst driving to work the SI drive kicked itself out of Sport# and into default Sport. I tried switching back to sport# and again after a few seconds it went back to sport. I had a busy day going various places so couldn't look into it much, but driving back home finally late last night I noticed the heater stopped blowing warm. Immediately checked the temp and it was climbing over 90 and approaching the top of the gauge. This morning I checked the water and found the expansion tank pretty much empty. I topped it up, ran the car and couldn't see any leak, but the car was still over heating. Checked the radiator which released a lot of pressure and air, figured it was air locked, topped up the radiator too and car ran fine at a steady 90. Hopefully, water issue sorted, but with no sign of a water leak I'm concerned where the waters gone, checked the oil and no signs of the head gasket going or oil water mix. My big question is to do with the SI drive though. Water leaks I can sort no problem, but electrical faults can be a nightmare. Is the SI drive so smart it realised immediately that the coolant level was dropping and wouldn't let me drive it in Sport#, the most aggressive setting, to help prevent potential damage. Or do I have an electrical issue here with the SI drive as well as the water. I won't have chance until next weekend to look at it further, so just wondering if anyone can shed any light on this is the meantime. It only seemed to kick me out of Sport# above 60ish mph too, at lower speeds it was happy enough in sport# it seemed. If not related to the coolant could it be diff?

Thanks for any input or feedback.