Weird Electrical in 97 Crew Cab 1 ton

[hraney]

1st thing in the morning I show 14 volts. As time (and temperature) wear on, it drops to barely above 12. Headlights are dim. Voltmeter needle deflects everytime the blinkers hit. I just put a new Alternator on this truck because of this issue.
Honestly, I haven't searched out all the grounds yet or done the yearly corrosion patrol on the stacked battery cables, but I never had this on my 95 6.5. It would just start cranking slow when I was running on one battery. Anyway, any suggestions for my next weekend foray into this issue?
Thanks,

[sschevelleman]

I say bad ground. Check the engine, body and frame ground connections.

[Scrufdog]

check/clean/add grounds. Clean both ends of all battery cables. Check the engine ground on the rear passenger side head.

[hraney]

Just for informational purposes:
I got into this problem last weekend. I pulled all the underhood grounds loose and cleaned them (they looked pretty good but, I was there). I also cleaned the battery terminals (they looked good too, but again, I was there).
Now I show a full 14 volts even w/ the headlights on. I am still not satisfied w/ the headlights (dim) and I am thinking of running them through some relays.
I have seen a couple of relay "Kits" on the web... anybody used/installed one of them?

[Garth J]

Hey I put in those GE Nighthawk bulbs what a difference I can actually see at night

[3bals]

I had a simular issue and it turned out to be a bad battery. I was convinced that it wasn't as I had just replaced the battery a few days before. Just for fun, I checked the battery and found it frozen. (things freeze here in Minnesota in the winter). Another new battery cured the problem.
Just a thought,
Jody

[sixnickel]

I have headlight boosters on both my 99 Sub and 00 K3500 The difference is like day and night. I can see on low beam what I use to on hi beam. Also I have it set up so the low beams stay on with the high. I tryed hotter bulbs first, it helped but the booster made the big difference!!! The only problem is in the rain they are so bright that sometimes the reflection off signs can blind you.

[njdevi11]

If your having problem with low voltage you need to test power coming off the alternator directly, find a good positive source like the battery cables or th stud on the back of the alternator. If you have 14v there and 12 on your gauge you need to check your grounds and check for breaks in any of the main power harnesses. If you have 12v there its time to get a new alternator. if you pull it you can take it to advanced auto and get it tested on a bench tester. I got a new one there for $100 and it comes with a lifetime warranty.

As for the headlight kits, i've seen them online, pretty expensive, are they just relays? Relays are easy and cheap, (dare i say they're fun, you can make some interesting circuits with them) basically its a switch, there are 4 or (or 5 on some, the 5th contact is the "opposite" contact) feet on the bottom, the left and right feet are parallel they are ground and switched 12v (your old headlight power). these are your low amperage control feet, it does not matter which one is which. the other two are your high amperage relay. When low amperage 12v goes to the left and right feet, the other two feet are electrically connected, so, run one of the perpendicular feet to your headlights and the other fused (40amp i would go with) directly to your battery.

If you've got any questions on relays let me know, i can wire some fun stuff with them like momentary toggles, override switches....

[hraney]

Ok, sorry to revive such an old thread but....
Finally got around to really checking out my "low voltage" issue. Everything under the hood checks normal w/ regards to voltage and amperage in the charging circuit. I added 3 grounds to the system and they made no difference. I changed the headlight switch w/ no diff (found some splices in the harness to it so previous owner had some issure there). Everything under the hood shows me to be charging at 13.8 to the batteries. If I put a weak voltage on the field wire, the alternator loads up properly. I show to be pulling a tick less than 60 Amps total w/ everything on. So I guess the real issue is with the guage in the cluster. But at least now I know. End of the day today I had some more info on the truck and I now have batteries w/ top post and side terminals w/ a good cable running between the 2 Positive posts. I will replace the other side terminal cables later. I also plan to add a guage set to it later on and I would still like to put the headlights on relays.