I had a 997 that i had wired directly to battery and had no issues then i decided i wanted to get rid of so maney wires on my battery and had a guy that installs them regurly put some things on my boat and ask him to wire it in under the dash so i could loose some wires and from that day on if i had it on and started my boat it would freeze up then i had to unplug it. so after doing this a while i decided to take it back to the bat. again and then no more problems.So i would say if you have it directly to your bat it could have a bad connection where they are conected at the end of the power cable that is on the unit it is only about 2 ft long therefore it has to be spliced into to get to your battery.