Started my truck the other day and my voltage is in the red zone, speedometer and tach move with the blinkers, windows take forever to roll up ect. The battery is fairly new, what are the other basic things I should check that would cause this?
First off I would disconnect the battery and bring it up to a full charge slowly! Then do a test on it to see if it draws down quickly. If you don't have a load tester then bring it to Auto Zone fully charged and ask them to check it for you. They do this free of charge so it's worth the trip.
If it checks out to be ok great if not replace it no matter where you buy it. Just be sure to get one that is for your vechiel, don't get the cheapest one.
Next before you install the battery trace down all your grounds. Start with the main one from the battery then check out the ones that should be from the engine to the firewall and the frame. Check out the ones in your trunk that goes from the wiring harness to the body. You should have at least one good one there. If you are unsure of weather or not they are good grounds take them off and scrape off the paint and use a cutting lock washer that has a bunch of sharp nibs that should cut into the paint and give you a good ground.
Next thing to check is all your light sockets. Rusty sockets can cause all kinds of electrical problems. Clean or replace them if they are really in bad shape. Don't forget to clean the bulbs too! If they are corroded throw them out and install new ones.
Now one more thing to check before installing your battery. Your starter should be checked out to make sure that the wires have good clean tight connections with no corrosion. Don't go crazy tighting down the wires to the post as most are made of plastic and they snap fairly easy.
Now after you have checked everything out install the battery and test all your circuits. If everything is bright and working as they should be Fantastic!!! If not then it's time to check the alternator. With the engine running disconnect the negative battery terminal, if the engine keeps running and in fact it increases in speed then everything should be good to go. If the engine dies as soon as you disconnect the negative battery terminal then you have a BAD alternator!!! Leave your battery disconnected. Go buy a new alternator, don't forget to bring your old one for the core charge and to match it up to yours. Installation is just the reverse, reconnect the battery, start it up and make sure that you have anyware from 12.9-14.1 volts at the battery with the car running. Clean up All your tools and enjoy your ride!!!
Different cars have different charge numbers at idle. So don't freak out if you're only getting 11.8 at idle. Rev it up and see the difference in voltage. Happy now? It should have been getting higher and higher as the ebgeng speed increases.
If you're still having issues with the lights your going to have to chase down each wire to find out why your having an issue. Be patient this can take time and could be your turn signal switch, headlight switch ect. Most likely its one of the things I mentioned earlier. Or you can give up and pay $400-1000 dollars or more to your local garage or dealership, myself I like a challenge and even after doing this for 45+ year's I still learn something new every day I pick up my wreanches!