I've seen a battery that died (It would support a very small current, but completly drop out when given any more of a load). I could press the breaks and the 4 break lights were enough to pull it to it's knees (Under 2volts from 11Volts. That could be a test if you don't have a volt meter. (I'm guessing the VX allows the break light to work with the key off). If the fusable link burned open, it shouldn't be intermitent.