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Topic Review (Newest First)
01-11-2013 10:09 PM
whynotthinkwhynot They should, but I thought it was on the other end of the wire. Earlier Focis used a 175a fuse. All it is there is to prevent exploding the battery due to a welded short circuit. Without the fuse or fusible link, someone who didn't disconnect the negative terminal could cause the battery to explode if the hot wire was to short against the engine block and weld itself tight. You'd have super hot sulfuric acid and hydrogen gas all over the place in about 2 seconds. Exploding batteries are not a fun learning experience even if you don't end up dead or disfigured.
01-11-2013 04:58 PM
braineatingalien I looked more at the wire and it turns out it has a fusible link on it that was fried. I replaced that to get continuity through the wire again. The alternator did test out bad. So I got a new one and installed it. Everything works again!

I am not sure if all foci have a fusible link but on my 07 focus hatchback it was right above the power steering tank.
01-11-2013 03:58 PM
whynotthinkwhynot I doubt there are any names I could call you that you haven't called yourself. I bet the next time you work on anything electrical in a car- you'll disconnect that negative battery terminal.

Have you checked to see if you definitely don't have continuity between the ends of the alt power cable? What got burnt when it shorted?

If you're referring to the 175a inline fuse in that cable, yes you can purchase something similar and cut out the old one. IMO, it wouldn't be worth it. What you'd save in money, you'd eat up in time, and likely pain and suffering. Not to mention you might cut the old wire just a tad too short and have to rig or replace after you spent a lot of time rigging in the first place.
01-11-2013 03:09 PM
braineatingalien Well the alternator was really easy to remove, but I made a mistake. I forgot to disconnect the battery and blew the fuse to the alt. Is that fuse replaceable or can I wire my own in? I don't really want to buy a whole new wire.
01-11-2013 11:31 AM
braineatingalien I have been monitoring the voltage through the cluster test mode for the last week and it works randomly while driving. I tried to wiggle test it and doesn't seem to make a difference. I am getting a few tools now to pull the alternator today. I will keep you all updated and thanks for the help.
01-11-2013 11:08 AM
1turbofocus The 2005 started a new type of ECU alt control at idle the ecu only shoots for 12 volts depending on load , engine temps and batt temps etc

Low voltage warning wont come on till 11.8 , proper working voltage is only 12.8

Then there is a timer that allows low voltage at idle then after a given time voltage comes back this time can be as high as 255 seconds so be careful testing the alt at idle

If at idle the voltage does not look right but at higher idle (above 1800-2000) voltage is correct this would be normal

Now saying all this the Alt has the ability to charge as high as 14.69 depending on load , engine temps , rpm , batt temps etc

01-11-2013 10:41 AM
whynotthinkwhynot Wow... talk about two seconds too late.
01-11-2013 10:40 AM
whynotthinkwhynot I agree, it's time to start planning on replacing the alternator. So far, the 05+ Focis don't seem to have alternator plug-in connector problems that are fairly common on the earlier Focis. I do not know why this is, and as those cars age it will surely become more common. There are ways to watch alternator output while driving, but it's more for curiosity at this point. You just need a new alternator. Here's where I make my plug for you finding a local rebuilder- because that's a trademark of mine. You support your local small businesses, also in my experience it is much cheaper, and more reliable. Local automotive electrical rebuilders are in every municipality. These businesses might disappear as parts swapping DIYers get wooed by lifetime warranties, so reap the savings and benefits while you can. I got mine rebuilt for $80.

To double check your alternator problems use the electronic odometer method and monitor voltage while you drive. This will tell you if you're having problems with losing voltage via the alternator while driving, low battery voltage before starting, or high alternator voltage while driving. High voltage can kill your battery, and is not good for the rest of the electrical system either.
01-11-2013 10:32 AM
braineatingalien Okay, thanks guys. I am working on it today. I guess I will check connections and if everything looks good. I will pull the alt.
01-11-2013 07:57 AM
rambleon84 My 2007 started doing that last year. The car would actually shut off once or twice at stops but revving it kept it alive long enough to get home. Then the next few days the car was back to normal. The telltale sign that it is going out altogether was when electrical things started not working right, even got a message on the stock head unit. Then it died on me while driving, all electrical shut off; gauges, lights, everything. I had the alt and battery tested, the alternator wasnt doing its job. Ended up having to replace the alternator, since then everything is back to normal 100% and happy again.

Similar issue happened with my sisters '07. Her shop said it was the battery only for the new battery to die on her while on a trip. Replacing the alternator fix the problem and she had been issue free for the past year.
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