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Topic Review (Newest First)
12-12-2012 04:09 PM
steveplatt28
battery

When i replaced my battery earlier this year i made sure it was a SILVER CALCIUM type battery, as original spec. apparently because of the way the alternator charges the battery it can destroy a normal one within the year. hope this helps?
12-10-2012 12:23 AM
sailor X2 on testing the whole system, as opposed to individual parts when you've got a head scratcher of an issue.

As I was reading through, I was going to recommend checking the "pigtail" connector & it's wiring as well, because this area USUALLY causes the type of problem you are seeing. It's the communication between the alternator and the ECU, and MUCH more likely an issue than the ECU itself.

The OTHER odd thing seen B4 here was an alternator that passed a quick test, but STILL had a bad diode, NOT too common....

Luck!

P.S. - an easy check to see what's going on with intermittent voltage issues, is to use a cigarette lighter plug to hook a voltmeter to so you can get a reading when the light comes on - sometimes easier than always driving around after setting the car to diagnostic mode so you can see it on the odo display...
12-09-2012 10:43 PM
Reefmonster
Quote:
Originally Posted by Eiron View Post
All of our electrical problems were finally solved with that fix. If you don't want to keep guessing, find somebody with the proper test equipment.
I think I'll just take your advice. I'll post back when I find out what it was so everyone can learn from it.

Thanks
12-09-2012 01:52 PM
Eiron From my recent experience, the top two suspects for me would be the accessory plug on the alternator (3-wire connector) or the positive battery cable. Oh, make sure you've cleaned the ground connection wires, too. When I had Advance Auto test everything, they told us the same thing: both the new alt & the new battery were fine. Their test equipment simply isn't the right stuff to trace the problem down.

In my case, I replaced the connector first & still had all of my problems. Taking it to an automotive electrical specialist (in this case, an R/V retrofit guy) gave me a way to test the entire system ($80). This provided him the info to determine that the positive cable had enough broken strands that it was killing both the alternator & the battery. He cut off the old terminal clamp & soldered on a new one.

All of our electrical problems were finally solved with that fix. If you don't want to keep guessing, find somebody with the proper test equipment.
12-09-2012 12:58 PM
Reefmonster I was thinking about the ECU, but this is wierd...It comes on at low idle or when I'm mid-[range, but when I accelerate sharply it goes off. Could the belt be slipping? Or could there be an issue with the belt tensioner letting the accesory belt get slack? Why would the light go off when I accelerate?

I replaced with a brand new Alt from Autozone, and I had O'Reilly, Autozone and Pepboys all check it and they all said that both the battery and alt were fine...anyone?
12-09-2012 08:59 AM
Tymes
Quote:
Originally Posted by Reefmonster View Post
I have an 01 wagon and I'm getting this now. The Alternator went bad and then the battery so I replaced both, but now the light keeps coming on and it's getting annoying. Any ideas other than those stated? I took it to Orielly and...Alternator passes, battery passes, both are new within a week. This is killing me! Could it be a bad belt or bad tensioner? When I rev the engine it goes off Sometimes...Frustrating!

Thanks in advance!
Could be a bad ECU, according to the Ford dealer here, sometimes when an alternator goes bad it can screw up the ECU that regulates the voltage. And for about $1600 you can get a new ECU to turn off that light. I have the same issue, created by a alternator within Fords warranty, but they deliberately put it off till it was 50 kms out of warranty so they wouldn't have to deal with that expense. I ended up installing a voltmeter to monitor the power, it flucuates between 13 and 16 volts, thats why my light is coming on and going off all the time.

And for the inquiring minds, Yes I tried going to Ford Canada and they backed the dealer, so yeah when this car dies I'll near buy a Ford again.
12-09-2012 03:12 AM
Reefmonster
Quote:
Originally Posted by Eiron View Post
Make sure your battery cables are all solid/intact, especially at the battery clamps. If you have broken wire strands at the clamps then that could be shortening the life of both the alternator & the battery. This happened on our '02 Focus wagon (went thru 2 batteries & 2 alts) & was only fixed after rebuilding the positive cable's battery clamp.

The alt-to-starter cable could also be a candidate for problems, but that cable doesn't usually see the amount of disconnecting that the battery cables do, so it's less likely to be a problem.
I have an 01 wagon and I'm getting this now. The Alternator went bad and then the battery so I replaced both, but now the light keeps coming on and it's getting annoying. Any ideas other than those stated? I took it to Orielly and...Alternator passes, battery passes, both are new within a week. This is killing me! Could it be a bad belt or bad tensioner? When I rev the engine it goes off Sometimes...Frustrating!

Thanks in advance!
12-04-2012 01:51 PM
Eiron Make sure your battery cables are all solid/intact, especially at the battery clamps. If you have broken wire strands at the clamps then that could be shortening the life of both the alternator & the battery. This happened on our '02 Focus wagon (went thru 2 batteries & 2 alts) & was only fixed after rebuilding the positive cable's battery clamp.

The alt-to-starter cable could also be a candidate for problems, but that cable doesn't usually see the amount of disconnecting that the battery cables do, so it's less likely to be a problem.
12-04-2012 12:34 PM
matmatician Finding a place that rebuilds alternators mat be a bit tough, there are only 3 that I've heard of in the Seattle area. I didn't look too hard, but it does seem harder to find than you'd think.
12-04-2012 11:08 AM
f_o_c_u_s i didnt really know there was another way to go besides buying them? a friend of the family is a mechanic and owns a shop with his dad, i usually go through him and i get a reasonable discount through advance auto parts. if there is a cheaper way to go about this though please let me know.

my stereo is completely stock except for my head unit. its a sony xplod. (apparently me and matmatician here have the exact same car ;) lol) which reminds me, i put my face plate back on the head unit this morning and went to plug my ipod in, after resetting everything (from disconneting the battery yesterday) my source button wont work on the radio to put the radio in aux mode. idk if its from the battery/alternator issue or just a coincidence.
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