Smart Alternator

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InSaneFisherMan

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Doesn't really apply to my boat, just didn't realize my truck had it. My vehicle calls it battery load management.

Smart alternator, are designed to be variable output and are controlled by the vehicle computer. Basically designed to improve gas millage and this system may not charge any auxiliary batteries through the 7 way plug.
 

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Been that way for probably 30 years now. Some even have a clutched pulley that totally disengages the armature when there is no load.

It should still respond to added loads like an external battery just fine I would think.
 
Don't know all the details, but my old '95 Dakota's charge output was controlled by the computer's voltage reference. Where the processor picked up the reference, I don't know, but I can see it not charging an aux. battery out on the end of a 7-pin trailer connector in that particular system.
(Whether that's "smart" tech, I'll not opine.)

Roger
 
Years ago, was in the remote woods of ON Canada, with a rental suburban. The gauge indicated that it wasn’t charging. Thought we were going to be stranded. Turned out to be my first encounter with a “smart” alternator.
 
Had to search my oweners manual, but I guess it will only help charge the aux battery if lights are on or the tow/haul button is pressed.
 

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Had to search my oweners manual, but I guess it will only help charge the aux battery if lights are on or the tow/haul button is pressed.

And Jupiter and Venus are in line with Saturn's moon Io, and your tongue is in the lower left quadrant of your mouth. "Smart" alternators.........HMMPH! What's wrong with having it charge whenever it sees a lower-than-reference voltage?

Roger
 
The best alternator were those that maintained the batteries as a priority, preferably a one wire or ignition triggered. These smart alternators are a problem the minute your trying to do things a truck is meant to do. My trailers were set uo to be towed with my then '79 F350, after that I had an '86 GMC C30, then a '90 Dodge D300, those were all good trucks, but I had to modify the charging system on my '95 F350 to get enough amps to handle my one trailer, and the '03 F350 that followed has been a royal pain as to maintaining the batteries.
If it sits for more than a few weeks, the batteries won't start the engine, The dealer tried everything, but no change, What I found was that if I'm going to park it for a few weeks, I need to hook up a charger and give both batteries a full charge. Then it'll be just fine for months. The alternator or regulator doesn't keep the batteries fully charged. Its goof enough to start it daily but they don't have the deep full charge they should.
I'm seriously considering finding a way to rig an old school voltage regulator on it.

Any added mpg you save with Smart Charging is lost on the cost of batteries it kills prematurely.
 
f it sits for more than a few weeks, the batteries won't start the engine, The dealer tried everything, but no change, What I found was that if I'm going to park it for a few weeks, I need to hook up a charger and give both batteries a full charge. Then it'll be just fine for months. The alternator or regulator doesn't keep the batteries fully charged. Its goof enough to start it daily but they don't have the deep full charge they should.
I'm seriously considering finding a way to rig an old school voltage regulator on it.

Any added mpg you save with Smart Charging is lost on the cost of batteries it kills prematurely.
I suspect you nailed the two-fold issue. With the advent of multiple on-board processors that have to be powered 24/7, and a certain amount of greed involved, "they" have figured out how to engineer things right to the point of being marginally usable, while generating as much profit out of parts replacement as can be tolerated by the market.
Call me a conspiracy theorist, but it sure seems that way far too often.

Roger
 
I suspect you nailed the two-fold issue. With the advent of multiple on-board processors that have to be powered 24/7, and a certain amount of greed involved, "they" have figured out how to engineer things right to the point of being marginally usable, while generating as much profit out of parts replacement as can be tolerated by the market.
Call me a conspiracy theorist, but it sure seems that way far too often.

Roger
They're not getting any money from parts out of me though. The way I see it if the OEM parts didn't last, I'm not putting the same thing back in there.
I'm also not paying the prices the dealer wants for batteries and other parts now that the warranty is gone. None of the OEM batteries or alternators were worth a hill of beans.
The truck was cooking diodes three times a year trying to charge batteries that were over taxed and starving for amps from the alternator which the dash refused to allow it to provide.
The next step is big changes I suppose of I'll go back to my old truck and let the newer one rot in the field.
What's bad is that years ago we didn't have these issues and the trucks were $12k. Now the trucks are $60k and they're a constant headache.
 
I bought a 250a from DB for mine, then tossed the regulator for an older Ford one.
Kick the 6g alternator to the curb and go with the older, 3g and never look back.
Be sure to run new, heavier, at least 4ga. cables to each battery too and run double grounds.
The wiring to the rear of most trucks is not set up to charge a discharged trailer battery, it'll maintain a fully charged battery that doesn't get run down but if your running a winch, or have a ton of accessories to power, you need to run some heavier charging wires back to the trailer with some sort of protection or battery separator. What I had happening was the trailer battery would get run down when running the winch, and the factory trailer wiring simply couldn't provide enough amps to keep it charged under load so it blew the fuse. After a few fuses it overheated the alternator when it tried to charge that rear battery, all while the two main batteries in the truck were fully charged. It cooked the main batteries, and eventually burned up the diode plate in the alternator. After five new factory 6g alternators I toss those and went with the 3g swap and higher amps. The cost of the new wires cost more than the alternator.

I'm not sure what's up with these new trucks lately but in the 80s and 90's my trucks always charged at 14.4-14.5v or so, now new cars seem to struggle putting out 13,2-13.4v or so. I checked the charging system on a friends new F150 and it showed only 12.9v and it was 3 days old. They call that charging? The battery doesn't even get enough voltage to be fully charged for a proper load test. Its not going to last very long running shy on voltage or amps like that.
 
They're not getting any money from parts out of me though. The way I see it if the OEM parts didn't last, I'm not putting the same thing back in there.
I'm also not paying the prices the dealer wants for batteries and other parts now that the warranty is gone. None of the OEM batteries or alternators were worth a hill of beans.
The truck was cooking diodes three times a year trying to charge batteries that were over taxed and starving for amps from the alternator which the dash refused to allow it to provide.
The next step is big changes I suppose of I'll go back to my old truck and let the newer one rot in the field.
What's bad is that years ago we didn't have these issues and the trucks were $12k. Now the trucks are $60k and they're a constant headache.

There's something wrong with your truck, that's not a complaint I've ever heard from other Super Duty owners.

I bought a 250a from DB for mine, then tossed the regulator for an older Ford one.
Kick the 6g alternator to the curb and go with the older, 3g and never look back.
Be sure to run new, heavier, at least 4ga. cables to each battery too and run double grounds.
The wiring to the rear of most trucks is not set up to charge a discharged trailer battery, it'll maintain a fully charged battery that doesn't get run down but if your running a winch, or have a ton of accessories to power, you need to run some heavier charging wires back to the trailer with some sort of protection or battery separator. What I had happening was the trailer battery would get run down when running the winch, and the factory trailer wiring simply couldn't provide enough amps to keep it charged under load so it blew the fuse. After a few fuses it overheated the alternator when it tried to charge that rear battery, all while the two main batteries in the truck were fully charged. It cooked the main batteries, and eventually burned up the diode plate in the alternator. After five new factory 6g alternators I toss those and went with the 3g swap and higher amps. The cost of the new wires cost more than the alternator.

I'm not sure what's up with these new trucks lately but in the 80s and 90's my trucks always charged at 14.4-14.5v or so, now new cars seem to struggle putting out 13,2-13.4v or so. I checked the charging system on a friends new F150 and it showed only 12.9v and it was 3 days old. They call that charging? The battery doesn't even get enough voltage to be fully charged for a proper load test. Its not going to last very long running shy on voltage or amps like that.

This is all true. The factory wiring is usually 8 gauge, pretty much only designed to charge a very small breakaway battery. Trailers with a big battery and electric jacks, winches, dump trailers, etc. need the wiring stepped up to 4 gauge because it's such a long run.
 
I've been reading here for a few weeks, just signed up.
This issue has been a problem for my '03 and 06 Superduty trucks for years.
The first thing I noticed way back when I bought the first one in '03 was that battery voltage seemed to be low all the time, at least compared to my '95 model.
The truck came with a single 105a Alternator about the size of a softball or so.
I had bought the truck to pull my trailers, both a small equipment trailer/car trailer and an enclosed car trailer.
Both have various accessories powered off the accessory trailer port, including both having onboard batteries that needed to be charged while in tow. With in a few months of buying it died on me on the road. Still under warranty they replaced the alternator saying it had 'burned up its diodes.
The new alternator didn't last but another week, leaving it dead in my driveway. The dealer installed two new batteries, an alternator and told me all was good, this became the story for the next four years. Checking it myself I noticed that it never charged above 13.4 volts or so, and that dropped to 13.1 with the lights on and 12.7 with the trailer on and lit up, and it dropped to below 12.5v with the brakes applied when four trailer brakes were active.

I take it back in for warranty and they tell me maybe its my trailer, so I took it in with the trailer, they tell me that its not designed to tow a trailer with an onboard battery and such a major demand, in short they blamed the trailer,
I borrowed a new trailer, a basic landscape trailer that my buddy had just bought and it did the same thing.
Keep in mind it never did blow the trailer or charging fuses that fed the trailer plug. The truck at this point still only had about 4k on it since it got used only to tow toys around.

This went on for 8 years, meanwhile I got the chance to own the 2006 model that belonged to an uncle who passed away, same motor, same configuration, same alternator. Same issues. I basically gave $5k for the truck which was then 6 years old with 900 miles on it at the time. It had sat for a few years since he hadn't driven in a while so I had to buy two new batteries and new tires for it but it was garage kept, as was my '03. It had never had an issue and had never been back tot the dealer other than for oil changes. It barely made the 300 mile ride home. I got back home with a check engine light and alternator light on the dash and a truck that wouldn't idle.
Still under warranty, it went back to the dealer, but the dealer here refused to work on a truck they didn't sell, seemingly pissed off that I had bought one elsewhere. I had to take it to a dealer 50 miles away.
It got towed there, and the other dealer said that it needed an ICP sensor, and that they were going to update the fuel pump and perform 9 recalls that hadn't been done on it. Then they said the alternator had 'popped' its diodes. so they replaced that too.
They had it for a month. I picked it up and was charged $100 deductible.
I drove it home, and didn't get 20 miles before it shut off on the road and had to be towed back to the dealer.
They get back to it the following Monday and called me telling me that the fuel filter was clogged up causing the pump to starve for fuel. The truck at that point had only about 1,200 miles on it and the only fuel in it I put in it at a fuel stop on the turnpike. They charged me for a fuel filter assembly and filter, $1,400, and I picked up the truck, it didn't make it out of the lot before it shut down. A tech came out and said its got an ICP sensor code. After a week, they called me and told me the new ICP sensor had failed, but don't worry, 'It happens' and they were going to cover it. Week three, I pick up the truck and it won't go over 40 mph, so back to the dealer again, this time they tell me an o ring failed in the new pump assembly and that too was under parts warranty. Week four. They call me and ask me if it was okay for the service manager to drive the truck a bit to make sure it was really fixed. Two weeks go by and the service manager calls and asks me if I had charging issues in the past, I reminded him that it was the main reason I took it there a month and a half prior. He tells me that the alternator, wasn't 'commanding' enough amps to the batteries and that over many miles, it slowly lost battery voltage and wouldn't start. They had the truck for 6 more weeks, they got the factory rep involved and even offered me a loaner car. They ended up replacing all the battery cables, the engine compartment harness, ECM, the trailer connector, and both batteries and the alternator again. The manager again said he was going to run it around for a week to be sure it was fixed. It wasn't.
Ford had authorized converting it to a dual alternator set up and they went ahead and did that swap, so it then had two of those mini alternators and the wiring that goes with them. But it only prolonged the issue. After nearly 3 months Ford says to replace the instrument cluster because they found a ,21ma draw on the system when the truck sat. They give me back the truck finally saying its all fixed and that I won't have any more issues. They 'wave' the additional deductible. They had the truck for four months and a week, and put 230 miles on it.
They even did an oil change because it was required after the ICP sensor and/or pump failure, twice.
The truck sat most of that winter, being used only a few times a month. I found it too discharged to start after sitting about 7 weeks one day, I charged the batteries and found it charing only at 13.5v, and it basically did the very same thing as my '03. I call the dealer and they tell me that 13.5v is perfectly fine and there's no problem. But if it sits for more than a week it won't start. The draw on the thing, which is minor, and half of what the draw on my car is, take the battery voltage down to only 12.6volts and it doesn't have enough reserve to start the engine. The same crap as on the '03.

The 03 meanwhile was going through batteries and alternators too, I was getting maybe 500 miles out of an alternator and a year tops from the batteries. After alternator #7 burned out, I found all the videos that were popping up online about these trucks having charging issues, just like both of mine were having.. I took the advice of several on Youtube and said screw the warranty and bought a new super duty 3g large frame alternator, which was basically what was OEM spec for the pre-1997 models, and I bought an aftermarket voltage regulator that took the charging control away from the ECM. Amazingly the truck suddenly charged the batteries at 14.4v and stopped burning up batteries and alternators. That was back in 2018, and its been good ever since. A few months later I did the same thing to the '06, on which I hunted down the single alterator wiring and bracket and converted it back to a one alternator set up using the same 3G alternator and regulator with two new batteries. It too has been perfect since.

It turns out that smart charging on these really isn't controlled by the ECM, the alternator is just crap and undersized. with the glow plugs on, which they remain on for up to a minute after it starts, the alternator has to supply over 140 amps to maintain a charging state., if not the batteries take the brunt of the load and if the truck isn't driven for several hours after each start the batteries constantly lose charge both killing the batteries and causing the alternator to work at its max output just to try and recover the batteries from each start.
Since I generally only drive maybe 20 minutes at at time, it never had the chance to fully recharge. Adding in a trailer and more load only made it worse. With the alterntor swap and two additional battery cables to the batteries, the 03 has now got almost 18,000 miles on it with no issues, and the '06 just turned over at 40,000 miles with no more issues.
The trailer wasnt the problem after all.
The way both of mine work is that the only part of the truck's electrical system thats required for it to charge is the completion of the charge indicator lamp circuit in the dash when the key is on, when the key is on, it sends 12v to the regulator 'waking up' the alternator. After this function also shuts down the alternator to prevent any draw from the alterntor when its not running. Jumping this wire to B+ will effectively make it a one wire system but will put a small parasitic draw on the batteries. I chose not to do that but they do explain it in the new alternator paperwork.

I won't get into which brand alternator I bought, I doubt that matters much but I did change out the original voltage regulator that came with the new alternators for one that was made in USA, this change gave me an added .3v to the output. Now after a cole restart, it recovers its battery voltage fully in about 20 minutes and brings the batteries to a full state of charge in about 40 minutes or so even after a cold weather start.
 
Query to Mirrocraft and Oilsmoke; Are all of these vehicles diesel or gas? I'm just wondering if it's a common problem associated with just the diesel engines.
My '04, 5.4, F150 hasn't given me any problems like what's been iterated here at all.

Roger
 
Mine are both diesel. I could see where a gas engine wouldn't have nearly as much demand on the alternator without the need to power the 150 amp glow plug circuit on start up for what ever amount of time needed due to temperature. If its cold they could be on for several minutes, even after it starts. That combined with the starter pulling 500 to 600 amps just to spin over the high compression engine. Add in the normal load of the ECM. and FICM the batteries end up being pulled own to about 10.3v at cranking and the alternator basically goes full field during the first few minutes after start up to recover.
The 5.4 dosen't take any more power to start than most passenger cars as that motor is simply a reincarnation of the old 4.6l used in the 90's Crown Vics.

When the alternator only makes 110 amps, if its cold and dark, its fighting a losing battle trying to recover until the glow plug relay turns the glow plugs off again.
What it boils down to is they put too small an alternator on these trucks, and too light duty wiring. The older 7.3L I had had massive battery cables, the 03 and 06 battery cables are half the size and the original alternator to battery cable was a single 8ga wire. With the new alternator I added two 4 gauge cables, one to each battery directly and I increased the ground wire to 1/0 cable connected to both the alternator bracket from the right battery and to the frame and body on the left battery ground. I also added a copper ground strap to the engine to the frame at the bell housing. The original ground wire was only a tiny #8 wire with both a lug in the middle to the body and another down to the frame rail. The right battery had a larger, about 4 gauge cable but I added a second one anyhow. All connections got cleaned and sealed as well.
 
And Jupiter and Venus are in line with Saturn's moon Io, and your tongue is in the lower left quadrant of your mouth. "Smart" alternators.........HMMPH! What's wrong with having it charge whenever it sees a lower-than-reference voltage?

Roger
Now, you'all go and see what happens when you turn a 22 year old whiz kid loose with
a computer and a set of (probably incomplete) sub-system specs to build vehicle software.

The only solution is to take him (the whiz kid) out to some place like Moab,
get his software project (the vehicle in question) on to the side of a slope 'bout a 1/2 degree of rollin ' over,
drain the battery down to around 7 or 8 volts,
jump start it, and see how the kid fares.
(make sure it's a manual shift with one or two spark plugs with the electrodes beat shut)...
(oh, and I almost forgot, disconnect the electric door lock control harness to high-side door after you lock him in)

I have a new Jeep with a transmission control module that needs this exact treatment...
(Shift into "D" on the ramp, give it bit of gas, let off the brake, and the g****nm thing rolls back into the river
with the stoooooopid "D" blinkin' at you)
I want my stick back!
 
Old Fart.....I've seen it. I'm a retired industrial maintenance electrician, but it wasn't a union shop, so we all did everything. I figured out that it was these college-"educated" mechanical engineers, that had NEVER turned a wrench in their lives, that was designing the stuff we had to work on. I developed the rather crass opinion that they should have to do an internship repairing machinery before they got the chance to sit down at a computer and design stuff. That way, they'd have the concept in their heads that somebody has to actually work on whatever they were designing.

Just another grumpy, old, opinionated S.O.B......Roger
 
Old Fart.....I've seen it. I'm a retired industrial maintenance electrician, but it wasn't a union shop, so we all did everything. I figured out that it was these college-"educated" mechanical engineers, that had NEVER turned a wrench in their lives, that was designing the stuff we had to work on. I developed the rather crass opinion that they should have to do an internship repairing machinery before they got the chance to sit down at a computer and design stuff. That way, they'd have the concept in their heads that somebody has to actually work on whatever they were designing.

Just another grumpy, old, opinionated S.O.B......Roger

Nothing crass about that. It is an excellent very intelligent idea! At a minimum "factory floor" guys should be consulted.
 
Query to Mirrocraft and Oilsmoke; Are all of these vehicles diesel or gas? I'm just wondering if it's a common problem associated with just the diesel engines.
My '04, 5.4, F150 hasn't given me any problems like what's been iterated here at all.

Roger
Mine is a diesel, 6.0L Diesel with a single alternator. Some had twin alternators, but I heard even those have issues with burning up one of the two alternators.
If these didn't have an issue there likely wouldn't be so many youtube vids and companies selling 3G high amp conversions for them.
The first failure on mine came as a surprise at only 2,200 miles, I hadn't even towed with the truck yet at that point, Ford replaced the alternator under warranty. At 2,350 miles it was dead again, Ford performed a recall, replacing the instrument cluster and again a new alternator.
At 5,300 miles it died again, this time 1,400 miles away from home. It got towed to a local dealer there where they replaced the Alternator, alternator harness, the complete battery cable assembly, and both batteries.
It drove home without issue. It sat for a month and a half that winter, when I went to start it the thing was nearly dead. I charged the 3 month old batteries, and used the truck, I noticed it not charging that day after it seemed to struggle while cranking. I got it home and the battery volts were down to 11v. It wouldn't crank back up. It went back to the dealer and they said all the diodes had burned up in the alternator and that they couldn't get their hands on one for over a week. They grilled me about how I used the truck, saying that if I tow a trailer with an onboard battery they've been known to do this. All of my trailers have small gell packs as part of their brake system, nearly all trailers to. They draw voltage off the B+ wire in the 7 pin trailer connector. They blamed it on that and didn't want to warranty the alternator. I called the Ford , filed a complaint and four days later I I got a new alternator and two new batteries from Ford. No longer being able to trust the thing I bought another truck and the '03 sat with then 9k on it. When I had the time I installed a custom auxiliary battery charging set up that limits the load at the trailer connector along with diode protection for the trailer accessory circuit. Its a system that was common in emergency vehicles with high drain components.
Between then and the next alternator failure I hadn't towed any trailers. It mostly sat except for a few short trips. I was pretty pissed considering this was bought to tow trailers.
After a 300 mile ride into PA and back it again was down on voltage and wouldn't restart.
At that point being out of the factory warranty by time, it checked it out myself, and again all of the diodes one the rectifier plate were burned up.
What I finally figured out is that the alternator was pretty much charging at capacity all the time, then when you did a few restarts in the cold weather it wasn't able to recover the batteries fast enough. That combined with the heater fan going, the a''c clutch latched on (defrost mode), and the headlights and maybe the fog lights on, all on top of the 90 amp glow plug relay draw at start up, the alternator was getting cooked. I noticed that it would heat up the B+ wire from the alternator to the battery pretty fast. I first tried adding a second 4 gauge cable but it didn't help much because the alternator was still trying to charge 110a all the time. The problem was it needed to be charging at least 162 amp or more to handle the load.
I put a large frame 250 amp 3G alternator in place of the original 110a 6g model along with a pair of 2 gauge charging cables, one to each battery. It fits under the hood but I had to notch out a section of the hood liner so tbe alternator fan wasn't hitting the fibeglass insulation. Its been fine ever since.

There are bigger 6g options but they don't have a good track record for longevity and the 3G is a proven design that's been around for decades. There's a dozen or so vids on youtube about this as well. Apparently even the trucks with dual alternators get convereted to a single high amp 3g as well to solve their issues. Some of these trucks have computer controlled charging but on mine, the alterntor rettains its regulator but is 'excited' via the instrument cluster through thee charge indicator bulb.

I found it odd that these trucks didn't come with a volt or amp meter, something that I added to mine in the way of a Scan Guage which gives me both codes and all engine information real time. It plugs into the OBDII connector and fits almost anywhere on the dash. I put one in all my trucks now.
 

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