Just picked up a 2000 24v and put 2 battery’s in it and it has a new alternator and I drive if for about 10 minutes and it pops up check gauges and the battery voltage gage stops working but I can drive the truck around all day so the alternator is charging the truck but not the batters and the battery’s will be completely drained and then if I shut off the truck it won’t start up without a jump I need help

 

Put a meter on the alternator output with the engine running. What voltage are you getting?

 

I’m new to this sorry but exactly how do I do that could I use a multi meter I have a battery charger that says alternator check so could I use that as well

 

Set your multimeter on like 20 volts DC. Red lead goes on alternator output, black lead goes to a good ground. (just about anything metal...) With engine running, see what the voltage is.

 

it’s 12.69 at the alternator and battery I’m waiting on the check gauges light to pop up and test again

 

Should be north of 13 at the alt, even at idle.

 

testes it again 12.18 for both now that the light is on and battery gauge is not working shut it off cranks right back up and gauge works

 

it’s a brand new alternator so do I need a new one

 

Have the new one tested. (take it off the truck, your local auto parts store should be able to test it.) If the alt tests good, voltage regulator is bad, which, unfortunately, is part of the PCM. (stupid design if you ask me.....) There are quite a few folks that simply switched to an external regulator, rather than replace the PCM to fix it....

 

is that the better option if pcm is bad and how do I go about getting a external regulator