Dual Battery Check

[stansloski]

Good morning.

 

I bought the pickup to pull a fifth wheel. I want to make sure that the second battery was isolated from the starting battery, so I don't end up with a flat battery on the truck if I forget to unplug the truck when I park.

 

It is supposed to be hooked up that way, but I wanted to be sure.

 

thanks

don

[davester]

Then yes, you would still need to follow the cables from both battery to see where they go, to determine if there is some kind of isolator preventing one from being drained or if they are just directly hooked up in parallel.

[wild willy]

I had a 2002 Tahoe that was factory equipped with a dual battery system. The two batteries were connected in parallel by cables going to the starter terminal. It was hard to isolate when one of them was going dead.

[Skimsucka]

.

[dewfpo]

To correctly measure a battery you should check it 8 hrs. after the last run and it should read at least 12.7V with the engine off. Any less and they are fading.

 

DEWFPO

[ExtraSlow]

Old topic, but in the factory setup, which battery is the primary battery and which is the "aux" battery?  I'm pretty sure mine are set up with the factory isolator in place, although I haven't physically located it.  At rest, the two batteries have slightly different voltages, but when charging, they are both charging.  

 

I do tow a trailer and camp for extended periods, so that second battery will come in handy.