The only way I know of to check the GPS pod is to look at the
GPS accessory view. It will show the status and what satellites are mapped.
IMHO, the most obvious thing, and the cause of 99.9% of ALL 12 volt electrical problems
is the battery. Load test it if you can. Even if it charges up OK, it may not be able to sustain any load.
For a quick check, you could find another battery to hook to your unit to see if the problem
goes away.
You could also bend the power connection and gps connection at the back of your unit for
a better connection. Only bend one side at a time or you will blow a fuse.
Good Luck.