ive always struggled with the connections starter contacts and batteries on my diesel truck

today i sit in my truck and put the key in the on position and my power is super low like i left something on all night ....anyways we take all the stuff off the batteries and the batteries are fine we tested them individually ...so i cleaned up all the contact terminals and and connectors and put it back on and the same thing.....but i maintain the terminals and connections every weekend and i havent had aproblem this is very sudden actually....the relays are all fine we even tried to rotate them around...i juts dont get it....THEN we hooked up the charger box to the terminals and they show that the batteries arent charged but when i test the batteries on their own with the needles they ARE what gives! im running out of ideas...the truck is charging right now for the next couple hours but im hoping for alist of things u guys have noticed over the years silly things that get overlooked or lil tricks to quickly determine what the issues are....oh yeah ps in the winter i changed the starter contacts so this is NOT a "click click" starter issue

Andrew

 

What do the batts, one at a time, show, when hooked up to truck circuit, in volts.
Clark

 

And, what was voltage each with no load(individually)
Clark

 

Sounds like you have 1 or 2 bad batteries. How old are they? Have they ever been allowed to drain completely?

Take them out again and have them tested by at least one or two parts stores with load testers. I'm not sure what test they've already gone through but a battery can show 12 volts sitting on a bench but when put under a load they "break".

If one of them is bad buy 2 new ones.

 

had same prob 1 bat probly bad the bad one may smell a little or be a little swollen best way is have them load tested seperatly

 

yep it was the batteries....the voltage individually showed 12.3 and 12.6....which is good...but the batteries just couldnt take on aload....the amps were no where to be found...2 new batteries and its a happy truck again...too bad i had to open the wallet though

thanks guys

Andrew