Have lately started to have a code pop up on my FM 1000 saying battery voltage too low.  It is talking about tractor volts.  If I check with a tester they check well over 12 volts with tractor not running.  I finally stopped and cleaned battery terminals and seemed to help, now it is doing it again.  What should I check?  When that code comes up, I lose auto steer capability until I clear diagnostic codes out of memory.  Thanks for info!