well first off hello yall sry i aine been around in a while.hope all is well with yall.
ok so i been haveing this problem with my truck and i have had my parents run all kinds of tests for me since at the time they are the caretakers of my truck.with my results im confused and thsi is why im turning to yall,the experts. first the truck wouldnt start so i thought starter.well starter is fine the batt's were bad.ok batteries replaced. so now they dont hold up acharge.but the batts load tested fine. and nothing inside is drawing power that can be seen or heard.(no radio) no lights left on no sounds when truck is off.but the truck has been started up everyday lately.then one day just bam,,,,batteries are dead and truck wont start.batteries get charged...same result.so now im thinking alternator. so i have my stepdad get batts charge and cranke the truck up.fires right up everytime on charged batts.i had him disconnect the batt's first batt disconect,no problem.second batt disconected truck dies imediately.so i think alternator for sure.but to be safe decied to have him follow thru on some more test. (when he disconnected that batts i had him only pull off the negative cables....positive cables still on the truck),,,not sure if thats correct looking back in hindsight..... so he checks voltage on the batts truck off.....12.70 volts.ok batts are good.....have him crank it up...fire right up,test the voltage.volts are 14.29....so the alternator is chargeing correctly....now im getting confused.have him turn the headlights on, the volts drop to 14.11 and do not come back up.but when he turns the lights off they go up to 14.17,,,,not the original 14.29? cables are fine batts tested fine.but according to this the batt disconect test says the alternator is bad but the voltage check says it is fine.so i just dont know where to go from here.im gonna have him do a battery drain test and try to crank her up and take off the positive cables and leave the negatives on this time and see what happens.can anyone help me? am i doing something wrong?or am i jus crazy here? thnx in advance........jr

 

Check your grounds. Make sure all your cables are clean. Anytime you take the battery cables off and the truck dies, I would look hard at the alt.

Good luck.

 

thats what i was thinking too.all the cables r good.does it matter if i had him take off the negative cables?would it die if u take off the neg cables even if the alt is good?

 

Sounds like you something drawing on the batteries after shuting down.. I would check for lights, including glove box, etc... My son-in-law had a remote starter drawing down the batteries.. And disconnecting the batteries while runnning is not a test for a bad alternator... the aternator needs a battery in the curcuit to work properly..

 

ok so chances r my alt may be fine then.specialy with it passing the volt test?im gonna have my stepdad do a drain test over the next 2 days and see where it goes from there

 

so what could be drawing power and not have any noise or light?

 

ok update.... on a drain test yesterday my stepdad left the truck hooked up and closed it up.the volts were 12.52 at the time.today after work he checked it and the batts were at 11.94 anyone know what can be causeing this?i had him disconect the alternator and he is gonna test volts tomorow to see if the alt was some how takeing power.im not even sure if this is possible tho