Greetings all, I'm new to the forum. I've been searching the web for answers to my problem and have come up empty. Hoping the folks here can help. I bought a used 863 G series, 1000 hours, serial# 514443283. For the last 3 months it has been locking out the BCIS system until it has warmed up for 15 minutes, I figured it was either battery or alternator, replaced battery in mid December, first time it worked great, after that it did the same thing. Two weeks ago it got to the point the BCIS stays locked. Pulled the alternator, had it tested, showed up as bad, replaced. With new alternator same problem, error code 03-10 voltage high. Alternator is putting out 15.5 volts. When I replaced battery in December I put the same size the previous owner had in. Since then I purchased a manual and realized the battery is undersized. Could this be causing the problem?
Welcome. Does the voltage reading change when at full RPM checking the voltage at the battery? If it is still 15.5 then iit could indicate that there is a problem with your Bobcat controller.
I haven't checked the reading at full rpm, I'll do that tomorrow after work. Is it the controller that tells the alternator how much voltage to put out?
Stranger things have happened in my experience. But one thing's for sure, if that main controller is seeing 15.5 charge from the alternator it's going to for sure flip out and send you a code.
You'll want to check it while the machine is off and running. If voltage the voltage is greater than 16.0 volts when off then your alternator is overcharging the battery. If okay when off, then check it when it is running at full RPM. If it is greater than 16.0 volts then your alternator is overcharging. If less than 16.0 volts then it could indicate an issue with your controller. Those are the checks from a reference for the G series electrical system. You already indicated you replaced the alternator and battery. Make sure you have good connections to the battery and the frame ground is good as well. The bad part is there is no easy way to swap out controllers to test.
BTW, my alternator output voltage on my G series machine is around 14.7 volts. If you are running 15.5 that might be too close to the 16.0 volt check the controller is making checking for over voltage.
In general alternators have an excitor wire also called field wire that energizes the iron core field. The more voltage that is sent to the field, the more magnetism and thus the more output. Full field voltage turns an alternator into a welder. This wire typically started at a 12v terminal of the ignition switch and had a lightbulb in series. They also usually incorporate a sensing wire that is to monitor voltage drop at the lowest point in a system like a distribution center or something. The lower the voltage drops when you use a winch or lights etc, the more momentary output. They can work fine without sensing wire but you need to have some way to vary magnetism inside the field to regulate output. I dont know a thing about 863s but an alternator is an alternator. Climb under and see what wires youve got on the back of the alt, where they go, what their voltage and continuity situation is etc. Itll help you figure out why your alt is going into welder mode. Does bobcat control alternator output via their own regulator inside ecm or something like that?
Where are you getting your alternator at?
Great news, the problem turned out to be super simple. After doing a little testing and wire tracing, the connector from the wire harness to the voltage regulator had 1 pin corroded away. Regulator was reading a completely dead battery and pushing out 15.5 volts. Replaced the plug and everything is running fine. Thanks all for the input.