I have been searching and I cant find what I am looking for.

My 99 dodge ram 1500 sport 4x4 is having problems charging.
I just put a brand new alternator and battery and battery cables on it.

when running the truck it never charges over 10 and as time goes it just drops, then we have to recharge battery and it'll start off at 14 and then as you run, it drops off, so means the battery is being drained and not being charged by the alternator.

does the truck have an external voltage regulator that can be changed out or what are some other things i can look at?

also i just put a new fuel pump assembly in, cuz the truck would not start for a while unless holding the gas, so we swapped that out and it runs now, also we just put all new plugs, wires, cap, and rotor on the truck and the coil pack was changed out last summer, so its fairly new as well.

Any input would greatly be appreciated. If you need more info, please ask away and I will get you all extra info that you need to help me figure this out. I am mechanically inclined and I do know alot about engines and everything, so I am sure I will know what you are talking about if you mention checking something or asking a question.

thanks ahead of time.

 

Have you double checked the wiring connections? If you have a new alternator and your system has no more than 10vwhile it's running, and drops from there, I would first check the wiring at the alternator. It needs a 12v feed to it to "excite" the alternator internals to actually produce a charge to the battery. Without the 12v feed to it, it won't put any voltage out. If all connections phisically look good at the alternator, check the voltages of each. There will be a small wire that feeds the alternator with 12v to make it work correctly with the ignition switch on. If you don't have a small wire with 12v on it, check where it connects to the starter and verify the wire connection isn't broken. I will see if I can get more specific info for you so this makes more sense.

 

In this thread you will find a service manual. Look around page 500 for the specifics on the charging system. If you use the index on the right side of the file, you will be able to quickly find what you need.
https://dodgeforum.com/m_340929/tm.htm

 

Did you check the fuses under the hood? There should be a large maxi-fuse between the alternator and the battery. If it's blown the charge can't reach the battery.

The large terminal off the back of the altgoes to the battery. You should have the same voltage there as at the batt terminals if connected right.
The 2 small terminals are for alternator control. 1 should have batt voltage while engine running and the other is a variable ground controlled by the PCM