WEIRD thing happened to me-strange power issues - Batteries?

[tubular031]

The 2 batteries in my truck are coming up on 3 years old now (I have only had the truck for about a year and a couple months)

The other day I go out to start the truck and all is normal. The truck had only been sitting for 1 day. The WTS light is on and fuel pump is humming. Then the WTS light goes out and I turn the key. It cranks and fires in about the same time as normal but the voltage gauge drops way down. Then it runs for about .5 seconds and dies. I do it again only this time the gauge is lower and same thing happens. The 3rd time the truck will not turn over and the lights are dim and the relays under the dash are clicking really fast. I think to my self, dead battery.

I go get my charger and hook it up to the drivers battery. After about 2 minutes the charger faults out and quits. I reset it and again after 2 minutes it faults again. I disconnect the drivers battery and the truck lights light up bright and I started the truck and ran it on the pass battery for about 1 minute. Then shut it off.

Sounds like the drivers battery is dead right? So I pull it out and just for the heck of it stick the pass battery in the drivers hole and SAME THING HAPPENS! Dim lights fast clicking relays, no start. So I put the battery that was in the drivers side into the pass side and start the truck off it only! Then I hook the drivers battery back up and with both cables hooked up dim lights, clicking relays and no start! WTF?!? I wiggled the battery cable around on the drivers side and the lights went from dim to bright. Then I start it up and drive off to my moms house. I get home later that night and park the truck.

Yesterday (1 day after this happened) I go out to start the truck and the batteries are only at 10.5 volts when the WTS light is on and I just hardly was able to start the truck, but it fired and ran. I let it high idle for about 15 minutes (1200 rpm on my chip) and during this time I was seeing 14.1 volts and 30 to 40 amps on the batteries. After I shut it off I used the clamp meter and showed no amp draw. So there is nothing pulling power when its off.

Maybe batteries? I don’t think a loose connection since the clamps were all tight but wiggling the drivers cable seemed to help only at first. I was not able to replicate the wiggling the wires to cause it to fail again.

[thbd77]

need to load test the batteries..could be a dead cell