I updated my MK4 system from 4-1/91 to 4-1/100 successfully. Unfortunately after updating, my system cannot find GPS signal.

I have checked the hidden menu that GPS receiver is reporting version 109.3, almanac is turned on. On the GPS satellite window I can occassionally see some activity on 1-2 satellites. For some reason it keeps changing only the last satellite channel where that activity can be seen usually, other channels are the same all the time. I have been driving around a good 30mins also but still no luck getting GPS lock my position.

What might have gone wrong? Thanks for your kind advise.