It is possible to read the last 4 reboot causes via an connected handset:
Menu -> *#05# -> handset shows ‘9‘ -> add 6762002 -> handset shows reboot exceptions
Menu -> *#05# > handset shows a ‘9’ > continue with 6 2 > continue with admin password >
Then handset will show the last 4 reboot exceptions.
The information displayed on the handset give information about where in the software the reboot happened, this information cannot easily be translated to a cause, for this we always need the developers.