Code P2503, low voltage?

EVANB813

MEMBER
2003 DODGE INTREPID
3.5L
AUTOMATIC
160,000 MILES

I got this car. I bought it from somebody. They said the car was fine. I changed the starter, and the battery, the alternator looks okay. It starts and runs but the battery light comes on within 15 minutes and the car shuts off, I have to pull in somewhere and swap batteries out just to get back home. They said the car sat for almost a year but it was okay. I have also bought three separate batteries for this vehicle. When it is running it runs smoothly but when it is about to shut off it idles high and doesn't kick into gears. What's wrong with this car? The only code to pop up was P2503 which is low voltage.

1 Reply

AL514

MECHANIC
4,795 POSTS

Hello, the P2503 is charging system voltage low, your Alternator is not charging correctly. You need to check the charging system voltage with a load on, such as the head lights, defrost, blower motor etc.
Also, check the connector on the Alternator for any corrosion or loose connections. Here are some guides to help. If you any need wiring diagrams let us know,
When you check the charging system, you'll need a basic multimeter set on 20-volts dc. And check with the red meter lead on the Alternator post (red wire) and the black meter lead on Battery Negative.

https://www.2carpros.com/articles/how-to-use-a-voltmeter

https://www.2carpros.com/articles/how-to-check-a-car-alternator

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