not charging mpv

[mbryson]

my 1990 mpv won't hold a charge. we have replaced the alternator and battery but problem still there any help would be appreciated

[12Ounce]

Do you have a voltmeter? They are very important for finding what is causing this sort of problem.

I prefer the analogue (needle indicator) type for auto work.

During engine idle, the post-to-post battery voltage should be 14+ volts. Anything less leads to problems. Measure another car's battery voltage just for reference. If there is low voltage, it will be caused by low altenator output or bad cable connections.

If the alternator voltage measures OK, but the overnight battery voltage falls to less than 12+ volts .. then the battery is at fault, or there is something draining the battery down.