Battery gauge pegged in the red, but the meter shows 14 volts on battery and alternator while on and off....

with the engine running use a volt meter to check battery voltage with the head lights on, should be around 14 volts on a 12 volt system, if 12 volts or less the regulator or alternator is at fault . if around 14 volts there is a drain or short, the battery could also be faulty.

How do you know it's only putting out about 1/2 ? an 1/2 what ? Amps or volts ? Did you hook up a volt meter to the battery posts ? red to red an black lead to negative post of the battery ? Does it show 13.1 to 14. 1 volts with the engine running , if so it's charging . The only thing that would cause the alternator not to put out full charge amps would be a bad diode inside the alternator or a power or ground issue. You need to check power an grounds doing a voltage drop test . Voltage Drop Testing the Charging System

start the car. if you have a volt meter at the battery you should have 13 to 14 volts while running. if not your alternator isnt working.

it may have deffective diode on the charging system(the alternator). 14 volts is an over charge in a battery. ampere reading must be on what the battery designed.

hello there:
you're problem may be in the alternator or the battery to find out you will need a volt meter and have the vehicle running to test the alternator set you volt meter to dc voltage and touch the positive side with the red lead and the negative side with the black lead you should show 14 to 14.5 volts if not replace the alternator then with car off using the volt meter and test the battery the same way you should get 12 to 13 volts then wit the volt meter still hooked up to the battery with the help from someone try to start the car and see if the voltage drops below 10 volts if so the battery might be shot....hope this is helpful best regards D.Jones p.s please leave a review thanks

check with a volt meter if u have 12 volt at the big lead on the back of the alternator engine off

if thats good start engine check to see if alternator is charging check the battery a good alterntor charges 13.5 - 14 volts, u may have a bunk alternator

Volt gauge in Instrument Panel Cluster sounds bad, just off a little bit. Would have to replace IPC, through dealer. That can be a little expensive, if reads ok at
alternator, would not worry about it. May want to have checked with a alternator tester at a dealer to be sure. hope this helps.

They have expensive tools and equipment to test alternators but you can get by with a simple digital volt meter. With the volt meter on DC voltage attach each lead to the corresponding terminals on the battery. With the engine running and all the electrical loads on (such as the head lights, radio, defrost, wipers, radio etc). the voltage reading should be between 13 and 14 volts. If you actually only have 9 volts then the alternator isn't charging and you'll have to look in to that more. The truck wouldn't be able to start or run very well with only 9 volts so i'd be willing to bet the gauge is bad or possibly a wiring fault.

It can, if it's not keeping the battery charged up.
Have it tested, or take a volt meter, put switch to 12 volts, put the leads on the battery terminals, red to red, black to black, if the the meter doesn't show at least between 14 and 15 volts, the alternator is bad.

use a volt meter while the car is running to check the main wire or large red wire coming off the back of the alternator it should read a steady 14 volts, the volt meter must be set at dc 10 amp settings, ground the black wire to ground or a metal surface some where on the car and touch the red probe wire on the volt meter to the main terminal of the alternator as i said it should read a constant 14 volts if it doesn't the alternator is bad.