Outer Limits 4x4 Board

Ongetting off the beach at stockton this weekend I opened the bonnet to connect the compressor and found my second battery to be boiling it is a deep cycle battery and they are connected with a piranah system> I beleive the regulator has failed and has cooked the battery but not really sure let me know what you guys think.

cheers eddy

Well that is from overcharging.

Just the second battery? If so then yes the system is cactus but if both it maybe you alt