Alternator Conundrum...

[flynnt77]

I should have known better than to even get out of bed on Friday the 13th.

My '06 Ranger Sport (3.0) started doing strange things last night. I was on my way to work when I noticed the AC was blowing a little weak. I started fiddling with it, checked my gages and saw the ABS light on. The headlights started dimming out. The gage cluster lights dimmed out. Master brake warning light illuminated. Radio started power-cycling. Then the fuel gage died and the low fuel light came on. And so on and so forth, until the only thing lit up in the truck was every warning light in the dash. I got it to a gas station and popped the hood, fooled with the alternator connections a bit to no avail. I left it there and caught a ride to work with another employee.

I figured the alt or regulator was fried and being ignorant assumed they were inseperable. I tried to get another unit and found out that the 06 Ranger runs a 135 amp alternator What the ham samwich?! And by the way, it's a special order part that NO ONE, not even Ford, keeps in stock, and even if they had it I would end up paying about $240 after I turn in the core.

Anyway, I was in a manic rage by then and decided I'd drive the truck toward the house till it died and walk the rest of the way if I had to. Funny thing is, When I cranked it up it ran fine. The alt was obviously loaded to the gills trying to charge the battery back up, but it did ok. About halfway home it started the whole slow death process again. I stopped, left it running, and wiggled the wires on the alt a bit. It loaded back up and ran fine. I had to do this three more times on the way home. I cleaned all the connections with isopropyl and reseated them, but this damn thing randomly fails until I get out and fark with it.

Is my regulator dying, or should I call a priest?

 

[slycer2002]

Not sure, but my money's on the priest. Good luck with that.

 

[Earl43P]

Don't rule out a loose serpentine belt (they stretch) or a bad belt tensioner.

Otherwise, it does sound like a bad alternator. Internal parts are available. In your case, I'd suspect the brushes are worn (usually just one of the pair is short). The voltage regulator holds the brushes, so they come out as an assembly.

I don't know which alternator you have, but here is an example: http://www.alternatorparts.com/3G_products.htm

Very little work to replace the VR and brush assembly. Takes longer to get the belt and alternator off the truck.

 

[flynnt77]

Don't rule out a loose serpentine belt (they stretch) or a bad belt tensioner.

Otherwise, it does sound like a bad alternator. Internal parts are available. In your case, I'd suspect the brushes are worn (usually just one of the pair is short). The voltage regulator holds the brushes, so they come out as an assembly.

I don't know which alternator you have, but here is an example: http://www.alternatorparts.com/3G_products.htm

Very little work to replace the VR and brush assembly. Takes longer to get the belt and alternator off the truck.

I checked the belt and tensioner, they look good. Now the hunt is on for a new VR and some brushes, per your suggestion. I'll let you know how it works out. Thanks for your input

 

[flynnt77]

It died entirely tonight. No amount of fiddling or profanity could save it. I'm taking the alternator to a shop to be checked out, just be sure, but I am fairly certain that it's the wiring. The backshell for the ISA connector has no heat shielding, it turns out, and the wires appear burned out or broken.

Talking with my mechanic (who has been working on Fords since he was a sperm), I found out that Ford has had this problem for years. I looked at the way the rectifier and regulator are mounted, and it seems to me that putting the regulator and ISA connector, which can be damaged by heat, smack in the middle of the hottest part on the alternator was a bone stupid idea. Engineers are the dumbest smart guys on Earth.

Correct me if I'm wrong, but if the alternator fails, or if any element of the charging system gives up and a loss of power generation occurs, shouldn't the red battery light in the master caution panel turn on to indicate a problem BEFORE the rest of the electrical system shuts down?! I know the battery light is there. I see it every time the vehicle POSTs when I turn on the key. Damned idiot lights.

/rant

 

[locovaca]

Engineers are the dumbest smart guys on Earth.

Or, they work within a set of given parameters and limited resources and make the best decision to maximize those resources. Most of the time the most limited resource is $$$.

 

[flynnt77]

Or, they work within a set of given parameters and limited resources and make the best decision to maximize those resources. Most of the time the most limited resource is $$$.

Still aggravates the hell out of me. If they know the problem exists and have for years, why continue to release new vehicles with the same design?

 

[kimcrwbr1]

alternator, regulator and battery all work together. Get the wires and connectors good and fully charge the battery then you can isolate the problem if any. Hopefully you didnt burn up any components. http://www.therangerstation.com/tech_library/chargetroubleshooting.htm
here is a link dont buy anything until you isolate the fault/s it could be one or all depending how long you ran it like that. All you need is a multimeter and some time read thru the procedures all the way a couple of times if necessary then attack. You can save alot of money doing the research first.

 

[locovaca]

Still aggravates the hell out of me. If they know the problem exists and have for years, why continue to release new vehicles with the same design?

My 2.3 has 150k on the original alternator and 120k on my 3.0. They don't all die early deaths. Nor are the regulators, brushes, etc. expected to last forever.

 

[backroad101]

Seems like working around the issue. Why not take the alternator to Autozone or Oreilly's and have them bench test it?

Autozone and Oreillys stock the 130amp alternator. I am assumning that is what he meant when he said 135amp. If not, 5 amp won't matter. I got mine at Oreillys and installed in less than an hour (including time spend driving to the store). If you can get it to drive, Oreillys also has a device that hooks to the battery and could tell if the battery or the alternator is bad while still on the truck

I would think the ease of replacing the alrernator would be worth doing it to see if that is your issue. If cost is the issue, get one from a junkyard and have it tested.

.

 

[flynnt77]

Fixed!

Problem solved. It was the connector. The Armature wire (large yellow one) was burned and partially pulled out of the backshell. The small Stator wire (grey one) was burned where a bend had come in contact with the back of the alternator. I got a replacement connector with heavy guage wire and soldered/heat wrapped/loomed/excessively taped it into place. Alt is cranking the power now.

The man I took the alternator to said it would cost me about 70 bucks to have it repaired. He gave it back to me today and said it was good as gold, charged me $8.50 and sent me on my merry way. If any of you live in the general vicinity of Florala, Alabama, there is a man here who knows his starters and alternators and is more than fair on prices. PM me if you need info.

So if you have the same problem and your test set is failing to flag the voltage regulator, check the continuity at the backshell to make sure the wires haven't pulled out or broken off inside. They are susceptible to heat damage, especially if the harness is stressed by improper routing.

A new backshell with heat shrink and all costs about $22.00 from Ford, or you can get them online cheaper. I am going to get an extra one and keep it in my roadside repair kit.

Cheers!

 

[2813josh]

hmmm good to know.