I have a 1994 Dodge Caravan V-6 3.0. My check engine light comes on when my Alternator is not working. I tapped the alternator with a hammer and it shut the check engine light off and it was working, charging the battery. Eventually this tapping with a hammer didn't work so I replaced the Alternator AND battery. One year later this is happening AGAIN!! I took the alternator off because it is under waranty and the parts store said I have a good alternator. What's my problem? Is it a wiring problem in the car somewhere? I Just DO NOT KNOW.

SOURCE: 1994 Dodge colt is having alternator problems I think.

it is a good indication. check the battery with a volt meter a charged battery should read about 12.6 volts dc with the car running you should be getting between 13 and 14 volts at the battery if you are getting 12.6 or under when the car is running you need an alternator.

SOURCE: '99 dodge grand caravan, 3.3ltr, battery light

you should have 14.5 +/- with the AC on you might have a week regulator or week brushes in the Altenator . but not enough at this time to cause a no start . but do have the alt tested (Load tested) at a parts store .

SOURCE: I have a 1990 dodge caravan that will not charge

use a volt meter and check the voltage with the engine off. should be 12 volts then check again with engine running it should be 13 to 15 volts if no then the pcm is at fault. the voltage regulator is inside the computer control and you will need to have it checked out at a dealership. if bad will have to replace the computer on van to correct the charging system. hope this will help!!!

SOURCE: on my 2000 dodge caravan

Start out by replacing the oxygen sensors. The electrical system and fuel delivery depend on the O2 sensor to be in perfect condition. If you still have these flashing and flickering lights after you replaced the O2 sensor then then next thing to replace is the ECU (also known as a PCM or vehicle computer) Click on the link below to view the parts you will need:

http://cgi.ebay.com/ebaymotors/OXYGEN-SENSOR-dodge-CARAVAN-GRAND-96-97-99-00-part-auto-_W0QQcmdZViewItemQQfitsZYearQ3a2000Q7cMakeQ3aDodgeQ7cModelQ3aCaravanQQhashZitem483c0afd29QQitemZ310244998441QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

http://cgi.ebay.com/ebaymotors/DODGE-CARAVAN-Engine-Computer-ECM-PCM-ECU-Replacement-_W0QQcmdZViewItemQQfitsZYearQ3a2000Q7cMakeQ3aDodgeQ7cModelQ3aCaravanQQhashZitem27b41765c5QQitemZ170525156805QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

SOURCE: 1993 Dodge D350 diesel alternator not charging

Hi, I will keep this short, but just a tip on the tester they use, I had one bench tested and it showed up it was good and the built in regulator was good also. Put it in the auto along with a $75 battery, and the discharge light was still on!!. So, I checked all of the charging circuit wiring finding nothing wrong, and put a rebuilt alternator on. Took care of my problem, the alternator was intermittent, sometimes charging when they checked it at Auto-Zone, but stopped putting out when I put it back on the car. I lived 16 miles from the auto store, so it was a pain going back and forth, plus the cost of gas!! I would change it out if you can at this time. I am sure this is what is going on if all looks good under the hood as far as wiring. Check to see if you have the 75 amp alternator fuse under hood also. It may be gone. Make sure the hot cable to the alternator and wiring plug is OK. Change it out and you will be good!
Sincerely,
Shastalaker7
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