2004 Ford Focus Alternator

BAD LUCK CHUCK

MEMBER
2004 FORD FOCUS
2.3L
4 CYL
2WD
AUTOMATIC
171,000 MILES

I have an alternator on a 2004 ford focus that has been work intermittently, some days working perfectly charging around 14.7 volts with all accessories on, then some days (today) not doing anything. I pulled the alternator and battery, had both load tested at two different shops and both checked out as GOOD! Cleaned all of the connections and replaced the three wire plug to the alternator, then reinstalled. Drove the vehicle all day with no battery light, no issues. Today nothing! I have established that I do have continuity from the power cable to the positive battery post and ground. I'm wondering if this problem could be related to a bad internal regulator, brushes, or some other internal issue that could cause intermittent performance. I'd rather try a rebuild kit over replacement due to limited finances. Please HELP! Thank you.

1 Reply

CARADIODOC

MECHANIC
33,726 POSTS

Off-car testing is useless because you already know the problem acts up intermittently. It has to be acting up during the testing too, and you can't know that on a test bench.

The brushes are the most common cause of an intermittent total failure. Usually when the voltage regulator quits, it isn't intermittent.

In the '90s Ford had a generator design that was almost as easy to work on as the Chrysler products, but they couldn't have that. Now there is a cover on the rear housing that makes the regulator difficult to replace. I don't know what's involved, but it should be less expensive than replacing the entire generator. There used to be a very intelligent "ground here to test" terminal, but that's buried too.