charging problems

[onetonride]

for some reason my truck will not hold a charge.... the batteries tested good, alternator too!! i replaced the inline fuse on the passenger side quarter panel under the solenoid... anyone have any idea what i should look at next???? your input is greatly appreciated.

 

[Optikalillushun]

so ur saying it is not charging or it looses its charge sitting over night? if the latter u have a parasitic draw somewhere.

 

[onetonride]

so ur saying it is not charging or it looses its charge sitting over night? if the latter u have a parasitic draw somewhere.

yes basically it will not hold a charge at all! i didnt understand the last part of ur comment

 

[MIDNIGHT RIDER]

Drive around to charge the battery(s), then park for the night and immediately dis-connect a cable(s).

Check voltage at each battery as soon as the cables are loose and write down your findings.

After sitting all night, check voltage again and compare to the previous readings.

If each battery still shows at least 12-volts, hook everything back up and see if it starts easily.


If it cranks easily and the voltage held up all night, then the battery(s) is probably not the problem.


Next night, dis-connect the alternator at the starter-relay; leave everything else connected; see what happens the next morning.

Still good, then next night dis-connect the wire that feeds the rest of the truck and see what happens.

Keep at it and the drain will show up.



In 99% of cases, it will be a dead short inside a battery, regardless of how it tests.

 

[Agnem]

Usually if the alternator has a shorted diode, it will be warm to the touch even after the engine has cooled down.

 

[Mr_Roboto]

Keep in mind that the batteries must be disconnected to test. The "big box" parts store jockies don't understand this.

If you test them hooked together you are doubling the CCA, so even a pair of bad batteries will test OK.

A battery tester gives a good / bad result based on the CCA that the operator enters into the tester (off the battery label).