During some cold weather I noticed that my truck was struggling to start. The batteries were the orignal factory batteries from 2004. So I figure they were likey getting week anyway. One morning they failed to start the truck so I went to the dealership and had them replace both batteries.

The truck started great for three days but on the third day after driving about 8 miles my ABS light came on and soon after the battery light along with all the rest in the instrument cluster.

Back to Ford and they ended up putting a new alternator. It was fine for 1-1/2 weeks then last night I noticed that the battery light was very dimmly lit. This morning the truck started fine (the battery light was still dimmly lit) and after a 15 mile drive I shut the truck off. It would not restart and I had to get a jump.

On the way home the ABS light came on again.

Any ideas? I'm now 800.00 dollars into this and I have the same issue I did two weeks ago. Help Please

 

sounds like a failed new alternator. been there done that.

 

Jumped it again and tested the voltage at the battery terminals. Both were at 10.2v with the engine running. How common is it to have an alternator go down within just a couple of weeks?

 

as I said been there doen that. ford parts are warrantyed for 12/12 so you should have no issue

 

Go back and get another new alternator installed for free!

 

Hey FourbynFord, been through similar problem, however I didn't replace my batteries when it started. I have a load tester and they check good on 4 different occasions before the passenger side batt tested bad. Two alternators (O'Rileys), two trips to the shop with the second one and a new pair of batteries all in less than 6 months. My alternator guy (yes, I have an alternator guy now) replaced the diode plate both times, this gets you new diodes and voltage regulator as a bonus, and cost me about $75 installed. My light seldom stayed on more than 5 min or so but did flicker often after the truck was fully warmed up. I never saw it glow or any other lights in the instrument panel on. The guys at the shop also said they do a pretty good bit of business with our city vehicles (police cars and ambulances etc.) and it isn't uncommon to see the same vehicle back multiple times. Their attitude seem to be "keep fixin it until it stays fixed" Sounds a little fishy at first but they didn't charge me anything for the second repair. There is an 85 amp alternator (most common) and 135 amp on the police cars and even a dual alternator set up for the ambulances that are available from Ford but the only difference seems to be the power output not the reliability. there is a thread in this forum (with pictures) where someone installed a huge alternator/cable system. Looked like a permanent fix likely done out of frustration. Additionally, it never hurts to tighten and clean all your connections don't forget the ground to the block and the positive to the starter. If you have cold start/engine power problems after you get your charging system sorted out, you may want to test you fuel injection control module (FICM). Problems with the charging system are pretty hard on it. Good luck!

 

Back from the dealer, they said it was a faulty altenator and the batteries failed (All of which had been replaced by the Dealer in the last few weeks. They put in a another alternator and 2 new batteries. Hopefully the problem is fixed. I will say it amazes me that from what I have heard that it seems to be some what common that newer altenators fail at such a high rate.

 

It's been a long battle for me but finally found the answer. The problem is that with just stock truck (mine is a 04, some basic MODs) and while the glow plugs are on your pulling almost 200 amps. That is why the voltage is low (10-11.5 VDC) for a short time. The stock 110 will top out at 125 amps leaving the battery to make up the rest. This not only beats up the alt but the batteries also. I have an amp gauge that shows this. Being tired of messing with it I broke down and bought a xp250 from dcpower (Thanks Bismic). Now my alt rated at 250 amps takes the 200 amps at IDLE (rated at 180)! My opinion is that this helps the whole system. No low voltage for FICM or the injectors and starts filling up the batteries right away. If you decide that is a lot of money, don't have the stock one upgraded. Make sure the one you get is a (what they call) Large Frame Alternator. Update the wire (piggy back) from the alt to the battery. Hope this helps.

 

Thanks Chromedom! I went through some headaches with my charging system a few weeks ago and am runnin fresh batteries and a repaired factory alt. No battery light yet but my OBD software says my "control module voltage" is varying between 10.7 and 13.9 volts while voltage at the OBD port stays between 12.9 and 15.9. I've been on a couple of road trips with no issues but I'm still eyeballin' that Battery light because of that 10.7. Just like you said, it low during cranking and a minute or longer after. Looks like some kind of modification may be in my future. Do you know what the application(s) are for the large frame alternator?

15.9 seems a little "hot" too doesn't it?

 

I to have a battery light flicker it will do it at startup or going down the road so whenever its been going on for 6mo
during the flicker my scangauge reads 12.5volts and up
both batterys and alt replaced in the last 1.5 years I know that doesnt mean nothing
checked batt connects they were clean and tight need to check the cables on starter and other grounds
where are the other ground locations

 

On my '06 250 the driverside neg goes to a bolt above the steering box on the frame,(bolt comes in from the top) and the passenger side neg goes to the front of the block (pass side) under a nut on a stud (stud goes in from the front) that holds the lines for the xmsn cooler/filter there is also a short jumper that goes from the same stud back to the frame (bolt going in from the top). It's all a little aggervating to get to.

 

15.9 seems high, is that hot or cold running? Cold will give you a higher number but not that high. Possible that the regulator is not quite up to par.

The large frame use to be used on the 7.3 I think. Than Ford went to this small frame that holds a lot of heat in it and in my opinion way too small amperage and size. Do a search on large frame alt and you'll find it. Beware of small frame that are built up to be high output they use smaller pulleys to get the RPM's up. The bearings are not able to take the extra RPMs.

 

thanks rusty
its getting a little dark here now Im going to give those ground locations a cleaning 2morro

I have a hydro cell tester I am going to try also and I uasully get it on my pant or something. hate that thing

 

I'm not sure. I logged data to/from work today but didn't graph the voltage at the OBD port so I just have a min/max. both runs were the same on max volts.

 

I'm not sure. I did a data log to/from work today but didn't graph the volts at the OBD port so all I got was min/max. It was about 30 min mixed driving each way and both runs were the same at 12.9/15.9. Might try again tomorrow.

getting late for me, I seem to be stuttering