We've got a 2012 F550 6.7 with 138k. It recently got a battery light. The batteries are right around 12 volts with the truck running or off. I also tested the output on the alternator and its not charging. I put a new alternator in it and still no charge. All the connections are tight and clean. The batteries load test ok. Where to look next?
View 4 RepliesI have a 2003 F350 6.0. I had a flickering Battery lt on the dash last week so I replaced the Alternator. People recommended I upgrade to the 2005 140 amp alt from my stock 110. I have a single alt system. So I did, today it died on way to work. Batteries were drained. Had new alt checked and its fine. So All I have is a wiring diagram from 99-2002 but it shows the plug on the alt with 2 wires, Lt grn/red from switched ign and Org/Lt Blu which goes to batteries. Org/Lt blu has 12v but Lt green/Red has nothing with ign sw on. I did check fuse 45 in Central J box and have power there. I did notice I have no battery Lt on dash when you turn Ign sw on, and never got the Lt this morning when it died. What Im confused about is do I have a PCM? my diagrams that only go up to 2002 model show it for a 2 alt sys but not for a single alt. I should have power on Lt Grn/red with ign sw on correct? Everyone said 2005 alt was plug and play, the elec connector is now pointed down, where it was pointed up on the orig alt, look to be wired the same.
View 7 RepliesI ve been noticing that the alternator isn't charging correctly, or at least it seems like it. We drive short trips sometimes two times a day, a mile or less. One day, night actually, I noticed it started to not turn over with it's usual enthusiastic sound. When the batteries get discharged to a certain point, the voltage at idle will be less than 12 volts. If I rev the engine for a bit, the volts jump up, but at idle it drops back to 12 or below. Seems to me that it should be at least 12v or above if the batteries are discharged, and more towards 12.5ishV if the batteries are fully charged.
After I put it on a 6A charger overnight, the voltage upon starting is above 12, sometimes over 13. But if the batteries start to dwindle down from short trips, the voltage drops to 12 or below at idle.
I did install the smaller pulley a few years back, and that worked massively. I couldn't get 12V at idle before installing the smaller pulley. But now it seems like I'm back to that same situation before installing the smaller pulley.
So, I m guessing that a alternator bench test is in my future? The batteries are fairly new, tho they have been down to nothing at least twice from boneheaded moves by yours truely!
And, I'm speculating that this charging situation contributed to the recent FICM replacement that I went thru.
I have a 06 F250 6.0 My battery light has been coming on. Doesn't stay on but I'm planning a trip back east and don't want any issues to occur. I was thinking maybe the batteries. So I stopped at the local Oreilly's Auto store and had them tested. Told the guy what it was doing and he said it sounded like the alternator. He tested it and said it was going bad. He also tested the batteries and said they were good. So I went looking for a replacement alternator and they have different amp sizes. So I'm not sure on what size the original one is and if the replacement should be a bigger size amp wise.
View 11 RepliesSo I have been having this little issue for a few weeks now. I will be driving along and out of nowhere my batt light will come on and my gauge cluster,radio and windows stop working and the ficim volts jump to 15.5-16.5. This is an intermittent issue. Yesterday I put my multi meter on the alternator and I am reading 13.5 or so this number was done at idle and the batt light was NOT on .
View 14 Replies2001 ranger with 4.0, alternator failed and new alternator is also not charging, showing very little output. i've installed 2 new ones with no fix. the regulator is in the alternator, correct? I'm stumped and not sure where to go with this.
View 14 RepliesOK I have 14.04 volts at the batteries with the engine running but my battery light is on. I had the alternator checked off the engine and on the engine and it tests good. Shows good batteries and good charging. Is there something internal to the alternator that would make the light come on even though the alternator is charging ok? Or is there something else that would make the light come on. This is on a 1999 F250 Superduty Powerstroke 7.3.
View 14 RepliesOne of my batteries on my van is on the frame rail. The box rusted out so I routed the battery into the back of the van for now. The van wouldn't start because the batteries were low. I charged the battery in the front engine bay overnight but it did not charge the 2nd battery, does that mean there's a disconnect between the two batteries? I thought they were in parallel.
View 2 RepliesMy alternator quit charging last night. Was pretty much a sudden onset as I was driving down the road and left off the accelerator the battery light came on and lights dimmed a bit. When I stepped on the accelerator again they bat. light went off and the lights came back up.
At idle I'm at 11.77v. I've pulled the plug on the back of the alternator and I'm getting voltage on both the red and green wires that go into the plug with the engine running. Is this correct?
Pretty much as the title says, I'm having an interesting electrical gremlin. Ford 7.3 super crew 2002 lariat LE.
I have batteries from 2015 that are losing their charge, both of them. It's like the alternator isn't charging them. Truck will struggle to start until jump started, then she's fine.
Symptoms are:
ABS light comes on when as best I can tell the batteries aren't getting charged. Not the battery indicator.
Now that the batteries are low enough, on the instrument cluster the little light the powers the mile LCD screen dims when it's not getting power (but it's fine when the batteries have charge.)
All accessories work when driving, but I haven't been able to drive a long while on the "not charging phase" to see how low they're go.
Batteries register dead (now) because they haven't gotten charge in a while.
When the alternator IS charging or "connected" I can leave the truck idle and she'll charge the batteries, truck will start just fine on the next run (no parasitic drain.)
Driving causes this to happen randomly, doesn't happen when I'm stationary, nor do I believe it CHANGES state (so if I'm idle it won't suddenly NOT charge if it was charging before.)
Narrowed down to 2 probable things.
Alternator
Bad alternator to battery cables
for some reason my battery light flickers when im driving regular and on the highway. I have had both batteries checked and they were at 50 percent charge and both were good so therefore I assumed it was my alternator. I removed alternator had it check and it passed all test. Everything was checked at o'reilly and autozone
View 8 RepliesThe past few weeks the dashboard warning light for my alternator/battery will occasionally light up while driving down the road. Whenever it does, my plug in voltage meter shows a healthy 14.x reading. It usually goes out after a few seconds, but will stay lit up for as much as thirty seconds. So other than voltage being too high or too low, what else will cause the dash trouble light to illuminate?
View 14 RepliesAlternator locked up in a parking lot. Replaced it and had to replace pigtail due to a loose wire in the harness. Now battery light comes on intermittently. New alternator is doing fine producing anywhere from 13.9v to. 14.4v. No output voltage correlation to battery light at all. The belt is still in great shape so I don't suspect slipping. Fortunately I caught the old one locking up almost immediately and had recently replaced the belt. Output voltage looks great. Are there any fuses for alternator?
Only thing I can think of that I did...when splicing in the pigtail that connects to the alternator, I briefly grounded whatever wire in the pigtail is hot. Was just a split second, but enough to see a spark and maybe enough to blow a fuse? I've seen people reference an "under hood" fuse box, but I don't seem to have one. My truck is a 2002 CC with just over 100k on the clock.
Had a bad alternator, changed it, and now the battery lite stays on all the time..Changed the alternator again with a known good one, and the light is still on all the time..
View 14 RepliesI just wanted to share with you all a cautionary tale about belt tensioners and idler pulleys. I am now a firm believer in installing the aforementioned items when you replace your drive belt. 15000 miles ago I replaced the drive belt and didn't heed the warning of some here on the forum.
For the last month or two I have noticed what sounded like road noise which I dismissed because I had just had new tires installed that had a more aggressive tread pattern than my previous tires, I also noted that the ECT had been a bit higher than normal, like running in the high 190's to low 200's on average.
Well while driving today I get the alternator warning light and lose power steering and soon after the brakes got stiff, this was followed by ever increasing ECT which got to 242* before I could get it off the road and shut down. It is too early to tell if the noises and the ECT temp rise were the result of this tensioner going out...
For what its worth the only tools required were a 10MM end wrench and a bit of skin to get the job done.
Is there a fusible link from the alternator to the battery? The new alternator that I put on and got tested is not charging the battery. Was wondering if it could be a fusible link but I couldn't find it. Where it is located on a 2000 ranger?
Also, I put a DC volt meter on the negative side of the battery and the positive side of the CHARGING wire that would be connected to the alternator and got the same reading as if I put the meter on the positive of the battery.
Does this mean the fusible link is good?
I have a 2002 ford taurus with a basic 3.0 v6 . The alternator stopped charging the battery.
New alternator
New battery
New pcm
Still nothing, this has been causing me the biggest headache. Alternator is pcm controlled btw...
My 2006 F250 has a single alternator and recently the charge light is on intermittently and I have watched output voltage fluctuate between 12.4 to 13.5 ... sometime a .3 volt bounce one way or another for no noticeable reason.
So rather than buy a new alternator, I would like to replace the voltage regulator and put in some new brushes.
What are part numbers that I need to pick up?
I had to replace my alternator (single unit) and after installation it seems only 1 of the 2 batteries is charging when I check them while the truck is running. What check or could be the problem?
View 1 RepliesTook in the alternator to get it checked and they said it was good. Put it back on and it seemed like it was charging according to my volt meter (14.24-13.5 v)
Today, it's not charging. Only reads 12.2 v while running. Is there a fuse or something I need to check? Grounds? It seems intermittent.
2003 F-250 V10 6.8 liter 255,000 miles.
Battery symbol light appeared on dash, After determining battery was good, I removed alternator and took it to have it bench tested at the parts store. It tested bad so I purchased a rebuilt alternator and had it bench tested before I left the store and it tested good. I installed it and it won't charge the battery. Tried a new battery...same thing. I tested the voltage at the battery and it reads 12.3 and the same with engine running. Engine runs until battery is drained. I removed the alternator and took it to a different store and they bench tested it good also!
View 8 Replies