Grand Cherokee 1999 brand new battery is draining in less than a mile

[Cpeck]

A month ago Jiffy Lube informed me I needed to get a new battery. A week ago I got a duralast from battery plus. Sunday I'm driving and my check gages light comes on. My battery is at 10V. I go to battery plus. They check the battery, and it's down to 9V by the time I get in there. They tell me what I also suspect, I've got alternator problems. They say nothing is wrong with the battery. I go to Firestone to verify my alternator isn't working. They tell me after a day and a half they can't find anything wrong with any of the electrical components. Alternator is just fine. What am I missing here?

 

[dwillys]

I'd check for a short

 

[k-2]

jiffy lube is OK for oil changes.
Firestone is OK for tires.

You need a automotive technician, I will take a SWAG - supposedly* the battery is checked and the Alternator is checked, BUT was the circuit between checked - maybe fusible link?

*Will need a second check

 

[JPNinPA]

Bad connection. I would be sure the terminal and connectors are clean. Then clean the opposite ends of the power and grounds. Grounds should be to the engine and chassis.
Use a voltmeter to check the battery and charging. Battery 12.6V engine not running. Battery 14.4V engine running.

Use the amp side of the multimeter to measure current between the negative terminal and negative cable connector. There should be less than 50mA.

Take the alternator to an auto store like AZ or O'R and they will load test it for free.

Consider if the alternator has brushes they may intermittently short before completely failing. Same with the starter it may short before failing.


Also be sure the battery is secure and doesn't move. And that the terminals do not touch the chassis.


JPNinPA
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