Potential CEM failure?

[volvooh]

My XC90 had been sitting for several weeks under about 15in of snow. When I finally went to start and run, my battery light would stay on. My iCarsoft was showing low voltage 11.5 v without the car running and with the car running just shy of 14 volts. Easy enough, I validated the bad battery finding with a battery test at Autozone, bought another battery and all seemed well. I drove the car to work the next day and go an anti skid warning. Thinking it needed to reset after the battery change I pulled off twice to do to shut-off, start cycles with no change. When I got to work to pull the keys out, the dash lights stayed on as if I was in the 1 position along with a red triangle (also a warning ding as if the keys are in the ignition). After a bit of fiddling, I disconnected the battery and left it till lunch. Hooked the battery up, no change. Drove it home, no change. Left the battery off all weekend and the same. Tried a different battery, same thing.

So far my diagnostics have been:
1) Scanned with iCarsoft for volvo. ABS and SWM both say no signal (replaced the SAS last summer and a faulty steering wheel switch last summer, btw). CEM says only "signal too high".
2) Disconnected the ignition switch, no change to the dash lights, still get the warning ding
3) Disconnect the steering wheel module, no change.
4) Used a different car battery, same result.

Funny thing is too that when the driver door is closed, it seems to shut off the dash. Open the door, the alarm dings and the lights come on. My fear is the CEM considering how long it was under snow during several snow falls, with warming and cooling in between and perhaps there was a lot of water intrusion.