Well on the way home tonight towing a 9k toy hauler my battery light started to come on and off intermitantly. Then after a while it stayed on solid for the two hour drive home. Never showed any drop in voltage on the volt meter.

Any ideas how to diagnose to narrow down the issue? I have a few ideas such as checking the trailer charge circuit fuse and the alternator output.

Any advice it greatly appreciated from the guru's at FTE.

 

I would say its a 98% chance you will be needing a new alternator sometime very soon!

Mine did the same almost 6 months ago and replaced the alternator and its never come back. I did check the harness on top of the alt to make sure it was connected well and it was, so alternator was replaced.

 

Samething happened to me last fall. New alternator was the fix.

 

Just start now saving for the batteries.. for me at least, they follow with in a month..

 

My battery light was on due to one of the two small wires that come out of the top of the alternator was rubbing on the alternator housing about 1 inch from the connector and shorted out.. two years ago.. Fixed the wire and it has been good ever since..
Also have read posts where the main wire harness that goes over the top of the driver's side valve cover also rub and short out causing a battery light..

 

2 years ago, my light came on, replaced the batteries, no change, replaced the alternator, no change took the truck to parts store checked alternator good light still on. Took the truck to an Alternator shop, they pulled the (new)batteries, fully recharged them and started to test the system. Fuse box first- it was a 35 cent 15 amp fuse that had blown. Charged me $15 to charge batteries, $35 dollars for testing and 35 cents for the fuse.
I'd check those first.
Fifthwheel01

 

Check the connections to your battery. Make sure they are nice and tight... and clean. Have your batteries tested by autozone or someone... Make sure you unhook them from each other for the test. Then while you are there test the alternator. Once the alternator starts to go it can take your batteries.. or vice versa...

Do this soon... once it goes out you can only go a few miles and your truck will shut down. The injectors use alot of power to run... then you will be replacing batteries and alternator... on the side of the road.

You ever make it over to www.nwforddiesels.com since you are a fellow Oregonian... LOL

 

Thanks for all the advice guys. I checked it out today with my multi meter and sure enough you guys were right like usual. No voltage coming out of the alternator. The battery cables are clean and tight. Batteries are only 5 months old. I got it home and will replace the alternator tomorrow or the next day when I can pick one up. I wont drive the truck until it's replaced.

Next question is go with 117.00 alternator or with one for 169-200 lifetime replacement one. Any idea's of other alternators out there other guys are running?

Layson: I didn't even know that site existed but I will head on over there now to check things out thanks for the heads up. If its any consolation the battery light came on right in your neck of the woods right by the Halsey exit 216.

 

I have the same problem except for mine only does it when I first start it. Comes on then goes out and back on for a few seconds. then it stays off have new optima batteries only thing I have found so far is the passenger side positive cabel has a crack in it as well as the neg. My 99 only has 24,000 miles on it. Does not come on while driving just started doing this a few months ago. Any ideas out there

 

Ive heard stories of the remans going bad and even with the warranty its just a pain in the azz. I went with a NEW one from auto zone for 209 and if it fails I get a new one in its place...

 

Yeah check it out. Every once in a while we have some get togethers that are pretty fun.

You were actually closer then you thought.. I work in Harrisburg which isn't too far from there.

 

Before you buy an alternator, these guys have some really nice high output units.

FORD F SERIES DIESEL TRUCK 220 AMP HIGH OUTPUT ALTERNATOR 02 03 8316: 8316-3-220 AMP ALT DB Electrical Starter-Alternator

 

Sounds like fun. I go through Harrisburg quite a bit heading to the dunes. You dont work for Monaco do you? Or do you know if their repair facility is still open right there by the Y at the north end of town?

 

Forgive my ignorance but what would be the advantage of having a high output alternator? I would imagine if you were running tons of eletronics stuff and huge systems I could see needing more power. I was reading the link and it said something about updating your charge wire to 4 gauge. Isn't that what is already on there? I know it is close to that it is a good sized wire. Thanks for all the info Kwik.

 

Thanks for all the suggestions guys. I replaced my alternator in a hurry yesterday and took a quick 250 mile one way test drive to Grants Pass not too far from where Clay is. All is good now and back to normal.
I had to rescue some friends of mine's hot shot truck. They have the dreaded 6.uhoh oh crap motor in their 03 dually. Well after the last 7 weeks in the shop they got it back and first trip down south it puked all the water twice and a few other problems so I brought down my truck ( ya know the old 7.3 keeps on ticking) so they could take care of their customers and I make some more money. Well I got a nice ride home in a F650 roll back with only 8k on the odometer. Man I was impressed with that tow truck we came up Sexton Mtn and wolf creek passes at 50 mph going up hill with that 03 PSD CC 4x4 Dually on the deck that was a lil top heavy by the way. Those are I believe (it was like midnight on the way home) 6% grades for 3+ miles each.

Again thanks for the help.