2004 Ford Focus issue - alternator, or just cold weather, or something else?

In January, I had the alternator replaced on my 2004 Focus after it died in the middle of the street. It’s been fine since then, but yesterday I was driving it and it suddenly seemed to lose power - the dashboard battery light came on, there was the dinging noise that indicates that a seatbelt is unbuckled or the headlights have been left on when you open the door, and the fuel needle dropped to empty (even though the tank was 3/4 full.) Then everything kicked back on. Then it happened again. This cycle repeated three or four times. I parked the car, restarted it, and after that it was okay. BUT - I have two long trips coming up, to remote areas of the Rockies, and I want to make sure it’s okay before setting off on these journeys.

It seemed like the alternator was bad, or maybe there was a loose connection, but I took it to the mechanic and he couldn’t detect anything wrong. The alternator is under warranty, so he’s suggesting that I just replace it, but also wants to run “other tests” to see what’s going on.

Of possible relevance: it’s been pretty cold out here for the past week (-5 F), I don’t drive the car that much, and it was the first time I’d started it in several days. The heat and radio were both on when I started it. I left it running in neutral while I scraped off the windows, which I usually don’t do. Generally I scrape off the windows first, then get in, start, and just drive. Sometimes it’s sluggish in the cold when I do this, but usually it’s fine.

Has anyone else had similar issues? Is it possible that this was just the cold? I’m wary of getting into a situation where the mechanic starts finding a bunch of stuff wrong with it that isn’t actually wrong.

Thanks!

It ain’t the cold. I can speak from having driven for over 45 years in cold climates, including three years in North Dakota.

It sounds like your mechanic is giving you good service. Let him chase it down for you, like he wants to. It’s worth the few bucks it’ll cost.

This Isn’t Normal. It’s Not Too Cold. Also, Starting And Let It Run While You Clear The Windows With Heater And Radio On, Isn’t A Problem, Either.

"It seemed like the alternator was bad, or maybe there was a loose connection… "

It seems like that to me, also. Did the mechanic check all wiring for alternator and battery, at both ends? There are ground wires that “ground” (attach) to the body and engine that need to be clean (free of paint and corrosion) and tight.

The trouble with diagnosing an intermittent problem of this nature is that when the mechanic does some testing, there is not a problem to find.

Since “I don’t drive the car that much, …” Is there a way to leave the car with the mechanic for a little while so it can be caught in the act?

CSA

I suppose that the alternator may have an intermittent problem but the fact that the gas gauge went down also makes me think that something else is causing the trouble. I would suspect power to the cluster or dash may have a problem. The alternator requires power that usually passes through the ignition switch and warning light that passes on to the field windings so the alternator can generate power. If there is a problem with the dash wiring then tapping on suspected trouble points like the connector to the dash may show up the problem area.

If the blower motor for the heater is on full blast while the vehicle is just idling, the alternator will not be able to keep up with the load. Same for low speed driving if the headlights are also on. Run the blower one speed below high and it should cut the load in half so the alternator can keep the battery fully charged.

But I would not rule out a loose or corroded connection on the alternator or one of the battery terminals. They are easy to check.

This doesn’t sound like an alternator problem to me. I think the battery or battery connections may be the problem or there’s something amiss in the wiring harness. If I had this problem I’d have the battery load tested and the charging system tested on the car. And ask they check the condition of the battery connections and battery wires and terminals. If everything checked out ok, I’d probably remove the alternator and take it to a place that has an alternator testing fixture. If it checks out good there too, and no repeat of symptoms, I’d just go I guess. Me, I’m sort of a worry wort so if I was venturing into wild wolverine country I’d probably purchase a replacement alternator and bring it with me. And if you see a wolverine, run!!! One thing is certain, they don’t make good pets, ask me how I know … lol …