So I installed a 2nd battery with a stinger sgp38 battery isolater in between about a year ago and now it seems like my second battery is not charging. I have my radio and accessories running off my second battery but my radio keeps shutting off due to the battery running below 11 volts. So this makes sense if the unit is shut off but to my knowledge this shouldn't happen when the unit is running and the alternator should be charging both batteries. So its worked for about a year now and all of a sudden its giving me issues. Any ideas what it could be? I am thinking its the isolator but not sure. Is there any way to test and make sure that its working and allowing the battery to charge from the alternator? Side note, the radio and everything works as it should when I charge the battery up but after going on a ride for an hour or 2 and listening to the radio it drains the battery. Any help would be much appreciated!
Do you have voltmeters on the batteries. If not I would check the voltage of the accessory battery before and after you start the machine.
I can try that tonight. I am thinking that it charges it but its just extremely slow. For instance, it will get down to around 11 volts to where the radio shuts on and off constantly so I turn the radio off and will ride around for about and hour with the radio off then turn the radio on and it will maybe play for 2 minutes if any. If that 2nd battery does get low when the unit is off as soon as I start it, it should be charging it enough to where the radio will work again as long as its running, correct? Im confused why this has worked for the past year and now im getting issues.
CumminsPusher
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I'm sure it's the ISO. Have someone fire it up while listening for the click sound because that one will do it if working correctly. If no click it's bad.
Might be a good time to swap that out to a voltage sensitive regulator (vsr) so it only allows a change to accessory batt after the start battery is full.
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Ill do that tonight and see if I can hear the click. Do you have any voltage sensitive regulators you can recommend? and why are they a better way to go?
CumminsPusher
Just a Honda doing Honda things.
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People all have there favorites but if you type in "vsr battery isolator" you'll find one at a good rate and they all do the same thing. I personally have the True unit. The one you have works off of key which is better for some things but a better isolation works off of voltage. When your voltage gets low a vsr (smart isolator) will shut off connection to your start battery allowing it to always be charged. So it alternates charge much better. What you have locks both batteries on at key on no matter what.
Both work but if you're replacing that imo might as well go vsr. And btw you won't need the positive trigger anymore from key or accessory. Everything else hooks up same so it's simple. 3 wires instead of 4
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