Intermittent battery light

DUANE HOFSTETTER

MEMBER
2003 FORD WINDSTAR
6 CYL
2WD
90,000 MILES

One day my van just drained out, but just before it did it said check charging system. Replaced the battery and was okay for about a week. Now the light and check charging lights come on. Alternator is only putting out 12.5 volts, but the battery still had a full charge. Could it be the voltage regulator or is it the alternator?

1 Reply

JACOBANDNICKOLAS

MECHANIC
108,192 POSTS

Hi,

When the engine is running, the alt should be producing around 14v. If you getting 12.5, there is an alternator issue. Yes, it could be related the voltage regulator, but it is internal with the alternator.

Here is a link that explains how to test the alternator. Try this and let me know what you find.

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

If it doesn't meet the specs indicated, I would suggest removing the alternator and having it bench tested at a parts store. Most will do it free of charge.

Here is a link that shows how in general to remove and replace an alternator:

https://www.2carpros.com/articles/how-to-replace-an-alternator

Here are the directions specific to your vehicle. The attached pics correlate with the directions.

______________________________

2003 Ford Truck Windstar V6-3.8L VIN 4
Procedures
Vehicle Starting and Charging Charging System Alternator Service and Repair Procedures
PROCEDURES
REMOVAL
1. Disconnect the battery ground cable.
2. Remove the accessory drive belt.

pic 1

3. Remove the generator electrical connectors.

pic 2

4. Release the wiring harness locator from the generator.

pic 3

5. Remove the bolts and the generator.

INSTALLATION
1. To install, reverse the removal procedure.

NOTE: Be sure to reinstall the ground strap to the front generator bolt.

____________________________

Let me know if this helps or if you have other questions.

Take care,

Joe

Images (Click to make bigger)