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Greenlee · 02-10-2019, 05:57 PM

I’ve been playing around with this multimeter trying some of the tests Hatzie suggested. My negative cables tested okay.

On the positive side, I changed the ring terminal connector on the positive cable lug that runs from the battery to the alternator just because I didn’t like the way it looked. Someone had put a new connector on it with a splice. I cut out the splice and put on a new terminal. The test from the positive stud on the alternator to the J-studs on the firewall was reading .031vdc. After testing for about 15 or 20 minutes with the head lights and key on, my battery lost enough power that it wouldn’t start the truck. I had just charged it overnight, so I decided this battery was weak and went and bought a new one. With the new battery installed I redid the test from the positive stud on the alternator to the j-studs on the firewall with the key and lights on. With the new battery I get a reading of .001. It’s interesting that I’m getting a better reading with the new battery!

I guess time will tell if I fixed the problem with it dying and losing keyed power, but I think I needed a new battery anyway.

02-10-2019, 05:57 PM	#20
Greenlee Registered User Join Date: Jun 2004 Location: El Lago, TX Posts: 1,668	Re: Electrical Gurus - 87' no keyed power I’ve been playing around with this multimeter trying some of the tests Hatzie suggested. My negative cables tested okay. On the positive side, I changed the ring terminal connector on the positive cable lug that runs from the battery to the alternator just because I didn’t like the way it looked. Someone had put a new connector on it with a splice. I cut out the splice and put on a new terminal. The test from the positive stud on the alternator to the J-studs on the firewall was reading .031vdc. After testing for about 15 or 20 minutes with the head lights and key on, my battery lost enough power that it wouldn’t start the truck. I had just charged it overnight, so I decided this battery was weak and went and bought a new one. With the new battery installed I redid the test from the positive stud on the alternator to the j-studs on the firewall with the key and lights on. With the new battery I get a reading of .001. It’s interesting that I’m getting a better reading with the new battery! I guess time will tell if I fixed the problem with it dying and losing keyed power, but I think I needed a new battery anyway.