Posts: 433
Location: Cedarburg, Wisconsin | 11.7V is way too low at the unit, it wasn't designed for that. It most likely has a 12V regulator inside to keep the voltage constant internally no matter what the battery voltage rises to. Your battery should be at 12.67V or higher when it is fully charged. Take a volt meter and read directly across the battery. If it is 11.7V there when fully charged, it is junk. Next, read from the + terminal of the battery to the - lead at the unit. If it reads more than a tenth of a volt less you have some bad wiring from either a poor connector crimp, or oxidation. Do the same with the meter on the - side of the battery and go to the + lead at the unit. Same thing there, if you read more than a tenth of a volt less the wiring is a problem. The previous advice with a bad fuse connection is the first place I would look also if the + wire is the problem. Any place the wire has connectors, switches, fuses or other breaks is suspect. Another possibility is the wire itself may have been damaged, getting broken inside the insulation, adding lots of resistance. Not likely, but possible if everything else checks out. Last possibility is that the unit is defective internally.
When doing voltage checks like this I usually have a friend hold the meter lead on one end and add a jumper in to get the extra length on the meter leads if needed. Not fun, but it will tell you exactly what and where the problem is. |