Powerstroke 6.0 - That Darn Battery Light
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- เผยแพร่เมื่อ 12 ก.ย. 2024
- While this video was done last spring, I kept it unpublished as I was going to redo the voice over. With winter coming and personal issues holding my videos back, I decided to make it public.
Due to factors beyond my control, I cannot guarantee against unauthorized modifications of this information or improper use of this information. I assume no liability for property damage or injury incurred as a result of any of the information contained in this video. I recommend safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond my control, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user.
I got tired of frying my factory alternator. I ordered a high output alternator from Tucson alternator. These trucks pull too much current at start up. 370 Amp unit with smaller pulley and extra power cables to both batteries and Xtra grounds. Been on this new alternator for a year. No more problems. Luv it.
Cool. Glad it's working out.
This video is outstanding. Well done sir. Not enough DIY videos engage on a technical/procedural level like you have. As a 6.0L enthusiast and self made mechanic, it is information like this that can save you many headaches and wallet breaking shop time. Thank you for your work, it is well appreciated.
Wow, thanks!
You are the man thank you. Please make more 6.0 videos. You're helping people big time
another great video, thank you. My battery light came on and i immediately thought batteries. They were 2 year old motorcrafts and always were maintained on a trickle charge. Took them out and gave them a load test. They barely passed, so I brought them back to O reileys and they charged and tested and said they were fine. So i pulled up your video on the battery light, and tested the alternator wires like you described. I was worried about wiring due to an issue 2 years prior with a rat that chewed some wires which left me stranded in the AZ desert as the truck died and the entire instrument cluster went dead (story for another day). Everything passed so i knew i didnt have a wiring issue from battery to alternator and alternator to instrument cluster. The alternator on my edge monitor always was in the high 13v range that's why I initially thought batteries. Well, I did have a new spare DC power 185amp alternator that i installed, and the light went off and I notice charging consistently in the low 14v range. Took the 2 year old 110a weak napa alternator for an exchange (lifetime warranty) and now its my back up. thank you very much for the informative video.
You have such clear and concise videos and the presentation is done so well. Please keep it up! There are many videos on this platform but only a few channels (that I have seen) really help people come to an understanding of what and why things are happening, and what they are doing.
Thank you for your comment.
Its both... Alternator is underspec at 140a hot idle. Navistar 365 has a 220a alt. The Inductive heating strategy for the FICM draws over 150-200 amps on cold start. And then takes 2 hours to charge back what was lost. Repeated short term driving will cause FICM damage. Also the ground and positive leads between batteries are under spec to transmit power evenly. PCM and FiCM draw mostly from drivers side. Starter draws from pass side
You might want to take a look at my other videos about alternator testing and ground wires. I do agree this should have had a 160a alternator due to the startup, but diminishes.
Interesting that the driver side has more load
Where do I start? This video and your following videos (on grounding) along with a recent call to FICM Repair has my mind going 100 miles an hour. I am currently installing a Leece Neville alternator and upgraded battery balancing wiring, along with two new 850 amp CCA batteries gotten on warranty after a failed alternator and battery issues.
I have a 2006 F350 6.0 that I have owned since new. For the first 8 years and 120K miles the truck was the best vehicle I had ever owned. Since then I have just wanted a truck that "ran like it used to". I never have wanted more truck, just reliability. The past 58K miles have been a reliability nightmare. I have run the truck on synthetic oil since brand new and have worked hard to keep up with maintenance. The truck is mostly stock with a stock tune. I have made a some upgrades seeking reliability (oil bypass filter, coolant bypass filter) but mostly stuck with stock. I am simply seeking reliability, not increased performance.
Most reliability problems seem to have started in 2014 at around 120K miles. I recently noted that at 122K miles the alternator was replaced. Since that approximate timing the truck has had several sets of batteries, a new starter, repeated injector issues with replacements, a FICM issue and before any signs of failure I invested in having a new head gasket, ARP studs, Bulletproof EGR and blue spring done. Not long after the major rebuild, the truck was nearly unusable for a year with an intermittent short in a 12V reference voltage that was used by several sensors. When the reference voltage shorted while driving, the transmission would slam into lower gear. If the reference voltage shorted before starting, no voltage would be sent to the starter leaving me stranded, a built in protection of the design. The shop taught me a way to bypass this fault condition supplying voltage from the battery to a certain wire if I was stuck in the mountains somewhere. A year later and several shop trips, this problem was traced to the Mass Air Flow sensor that was intermittently shorting the 12V reference voltage. Even then the problem showed itself momentarily, but would not repeat. I had a bit of an "ah ha" moment in one of your videos when you showed the location of the Mass Airflow Sensor ground.
I have been in the mindset that I have been battling "engine" issues or should I say mechanical issues. Over the past week, I believe now my problems these past years may be far more related to electrical issues. I am now chasing the grounding points, cleaning them or replacing the wires and adding dielectric grease. I will be checking current carrying capacity of critical wires as well. I will add cleaning of the grounding points to my maintenance schedule every 4 to 5 years.
This reminds me somewhat of a starting issue with a forklift we had at work in the 1980s. We had a tech onsite to repair it, even had it trailered into a shop. It was returned with the problem. A lot of time and money spent with no results. I finally decided I would take a day off from my responsibilities and finally traced the issue to a wire grounded to the frame where the frame was rusting. Under no load everything electrically measured fine, but this connection could not carry current when starting. I am now of the mindset that my F350 issues are of a similar nature but at a grander scale.
P.S. I live in a mild climate in the Pacific Northwest. No salt is used on roads, so frame corrosion is minimal.
Thanks for the comment. I hope it is as simple as a ground issue and get it sorted out.
Thanks for this, my battery light coming on after start has been driving me nuts. Thanks for having a serious no-nonsense style without the usual TH-cam BS.
2007 powerstroke. I left my truck sitting for 2 weeks. Came home and the batteries were very weak but it started. I drove to work and they did not charge and the truck wouldn't start. The battery light was on. I changed both batteries. The truck started but the battery light is still on. There were no battery issues before I let it sit. I will try your problem solving but was hoping it was something quick. Not to mention it is 115 in AZ. Thanks for the video.👍
While they used a "battery" icon, it only tells that the batteries are not being charged. Depleting the batteries can fail them, but always the first look should be at the alternator and wiring. We would have been better served if the used a lightening bolt, an image of an alternator rather than a battery, or the word Charging. Not the heat to be under the hood, stay safe.
I notice that your meter reads 14.5v once the glow plugs turn off. I've never seen more than 13.9 out of mine, with two new batteries, a new alternator, and good cables.
It won't even full field any higher. Its the fourth alternator. The first two alternators blew the diodes and the dash light stopped coming on, ever. I drove it about 5 miles one day and it barely restarted when i went to leave. I put a new Ford Alternator on it, that lasted a week.
Since new the truck had trouble sitting unused more than a week or two without the batteries dropping to 12.3v or so, at that point you have one shot to get it started or it just clicks. It only gets driven when I need it and it sits sometimes for months at a time, but I out a maintenance minder on the thing to keep the batteries up. It only sort of works.
After the second alternator I ordered a 250a unit online, it charged 14.4v when first installed, and was fine for a week or so. It sat for a while, and the batteries were again too low to start the truck. I charged both batteries, and they tested fine, but the alt would only hit 13.7v.
I complained and they sent me another alternator, this one did the same thing, it charged to 14.46v when first installed, then after a long road test the volts dropped to 13.9v while driving, a bit less at idle.
I tried two more new batteries but no change. If I full field the alternator, I get only 14.01v.
There is no draw on the batteries other than the normal memory drain, it has no more than my other truck or two cars. If I drive it daily, it acts fine but the volts read only 13.9. I added two power cables with the new alternator and two additional grounds, one to the block, one to the alternator mounting bolts. The dash is sending batt volts to the connector and the alt light works normally. At night, with the ac or heat on, with headlights and driving lights, the volts drop to 13.0 on the road, 12.9 at idle. I've tried various voltmeters and I've got a scan gauge in the truck as well. All read the same volts.
The truck was stored for 20 years, the battery and wheels were removed and the tank full.
I revived it last summer. Back when it was new I had some issues with it going dead while I was away at work. The dealer tried to tell me it was normal then but still replaced the alternator, batteries, and battery cables at 140 miles back in '03. I parked it at about 650 miles that summer. It sat in my heated and air conditioned house garage the whole time under a cover. I read on one of the forums where a few others were having similar issues but I never heard a solution. If I take the alternator out and test it at the parts store it makes 14.1v max, but only 13.9 in the truck. I figured that's just the tester's gauge being a bit off.
For the past four months I've been keeping it plugged in on a maintenance charger, but if I take it off charge, it'll only last about 9 days before it won't crank. Two new batteries though will fix it for a while, but eventually they too stop holding a charge. (The batteries lose the same amount of voltage even if I disconnect the cables.
One of the batteries i took out is on my porch, the other I used in my car, and its fine in there but it still drops in voltage, the car just isn't affected much by it.
I also found that the batteries do not continue to lose voltage, they go down to 12.2 and stay there, the drop ceases at that point, they never go completely dead. The one old battery, which was new four months ago from Ford, will charge to 12.77v and test at 851cca, yet if it leave it sit on the bench there it loses 0.1v per week till its down to 12.2v. A new battery, doesn't do that, but once in the truck, the batteries are somehow damaged and start loosing volts when they sit. I dissected the first 250a alternator and couldn't find any faults, all diodes were good. I changed out the regulator and it was back up to 14.5v. I tried that with the current alternator, and it too charged 14.5v, but after about an hour drive, it was back down to 13.9v and refusing to full field any higher. A fresh regulator and it was back to 14.5v.
I can't figure out what is screwing up the regulators like that, or what or how it also seems to damage the batteries somehow where they discharge on their own so fast.
The truck has no aftermarket items, its bone stock currently with about 710 miles on the odometer.
I recommend taking it to a good shop specializing in vehicle electrical systems. You've got an issue(s) that online comments won't solve.
The 14.5+ voltage from the Leece-Neville 230a alternator is a function of its regulator. Also, depending on how you measure voltage, you can have at least a 0.5v drop in the reading, especially from the PCM.
Most voltage regulators utilize a thermistor to reduce voltage output as the underhood temperatures increase to avoid overcharging the battery. It's not abnormal to end up in the 13.4-13.6 range, although that depends on the vehicle manufacturer's design intent.
Thanks for all the information on the battery light im having this problem now I've had my 6.0 for about 3 months now so im still new to it
There's a lot of good information out there; sites such as FTE and PS.org have good technical knowledge in their tech folders, although FTE does not have it categorized well.
Great video again. I wish our ficms weren’t so sensitive to damage from low voltage. Most people don’t know if they let their trucks sit for two weeks or so, the battery can deplete enough to damage the FICM on start up.
Excellent video. It's nice to see someone who is thorough in their diagnosis. Thanks.
Thanks for the lesson. 2001 e350 diesel Ambalance runs great. Purchased last year. Started everyday in the winter 2017-2018 but this year 2019 when cold less than 24 degrees it gives problems starting. It's like the battery drains after 8 hours in cold weather. Thought about buying new batteries new alternator and new starter. But after seeing your video I know now not to rush to judgement about changing the battery definitely need to check them. The thing about it it could be all three. The starter is fine but it's not a gear reduction it takes longer to turn over, not sure about the alternator when running voltage is at 13.9 - 14.1. I have a remote starter so I don't check the voltage when starting ( I don't want to see a dead battery), I thank I will today. Even on a cold day 17 degrees recently she did start on the first crank but that 3rd crank of the engine I'm not sure boost needed.
Thanks for the tips. Finally I can test my batteries. Found one bad. Light is out. Thanks
Glad to heaar you got rectified.
Fun to watch. Wonderful video👍👍👍👍👍👍👏🏻👏🏻👏🏻👏🏻👏🏻
YOUR VIDEOS ARE AWESOME! PLEASE KEEP THEM COMING!
sugarloafgee Thanks, will do.
Extremely helpful. Thank you...😀
You gave me a ton to rewatch and write down (or memorize on 2nd viewing). Last year I'd had a dead battery and after getting a jump I drove straight to a dealer to check, they declared bad passenger battery and replaced it. Last week my battery light came on (2004 6.0 diesel) and a few days later the dash started acting nutty, at one point the dash went dead, no gauges worked at all. I was too worried to try turn signals so I just limped home and connected to a trickle charger, then since the light remained on though the truck started fine and multimeter showed good voltage on batteries I thought it meant the other battery (driver side about 7yrs old) needed to be replaced so I did that - had no effect on the problems.
From your video, it seems likely I have a charging issue. Years ago I'd direct-wired two trickle charger cables, one to each battery, with their connectors sticking out the grill. At home I can connect a trickle charger to each connector. I hadn't been doing that lately, but due to this new problem I'm doing it each day. The truck starts fine, and volt meter says about 13.5 volts at the time I checked it, about 15-30 seconds after start, and after a short drive I checked both batteries with engine off, both had roughly 12.7 or so if I remember right.
So I'm still a bit confused. The alternator is definitely putting out power to both batteries, but maybe not enough to satisfy the battery light? Will have to watch again and think about that, since I thought your diagram showed if it is 12v it'll turn off the light and I have that much... I'll try your tests tomorrow. Came to youtube because I thought I was going to buy one of those jump starter batteries to carry with me, so I could jump start myself to get home to the trickle charger, and just keep driving with the battery light on. From your vid though, definitely seems I'd better at least by a continuous display volt meter so I can monitor I don't drop below 12v while driving. Darn truck, don't need this right now :)
teccec Your voltage 30 seconds running is good, but the light is not exactly an on-off switch, so you can still have an alternator issue or a wiring issue. Check the voltage at the trigger and move the wire around. Make sure it’s fully engaged. If you still light on if you must run the truck monitor the voltage real time so you know how the alternator is working, but I’d pull the alternator and get it tested, maybe a two locations. And just to be sure they are OK it never hurts to have the batteries tested. I check mine 3-4 times a year, but I’ve got a dozen batteries to maintain so it’s a routine process for me. The main purpose of the video was for people to not keep replacing good batteries or get to the point of hurting the FICM. Alternator regulators, brushes and diodes can cause some odd issues.
Thanks. Came back to write down your tests today. Guessing I'll be ordering an alternator tomorrow.
teccec When I get time this vid will be redone, for the vocal as well as other things. You can have a diode issue that despite a good voltage output keeps the light on. But it is failing.
Ripple voltage or (AC voltage) can be measured by switching your DMM to AC and connecting the black lead to a good ground and the red lead to the "BAT" terminal on the back of the alternator, (not at the battery). A good alternator should measure less than .5 VAC with the engine running. A higher reading indicates damaged alternator diodes.
Thanks. Instead of having a parts store check amperage I'm going to take it to a diesel shop tomorrow that said they'll test for free before the expected alternator replacement. I'll update the results here for benefit of any future readers who might want to know. I liked your vids that I checked out, watched several, you try to be clear about the what and why and how...
Great teacher! Thank you..
Thanks
This is an amazing video.
Thanks. I do hope it has helped many.
Great video, very knowledgeable serious video no bull crap Great video thank you
Thank you.
Are you a DIY or a Mechanic? I would love to bring my truck to you for diagnosis.
DIY on my own vehicles.
I watched this video and did what you say my meter is not digital but it shows everything good but light is still on help
Russell, then you probably have a bad diode in the alternator. Parts stores are not perfect for checking for this; alternator shops are better.
Great video thank you
Thanks, hope it helps.
clear and concise
Thanks.
Thank you sir
Your welcome.
wish you would make a video on how you moved the fuel pump behind the transfer case
I might be able to piece one together, but it was done over a dozen years ago.
What if the battery light is on during a cold start idle but turns off after I start driving? I think it's the alternator though one of my batteries was over charged last I checked
You can have the light on if there is a diode issue in the alternator. That can pass a higher voltage AC current then you are reading. Or there is just a voltage regulator issue.
good job
Great video you said 6.0 have 110 amp alternators but you also said yours was 140 amps. Is the 140 amp alt a repalcement for the 110 amp, if so could you name the brand and where you purchase it. Thank You
I have three that work, 110a (typical OE), a 140a Bosch (aftermarket), and Leece-Neville 230a (aftermarket).
The 140a Bosch AL7606N comes as a new alternator, best pricing RockAuto. However, Bosch only honors the if you state the truck is an F-450 or 550 . 6.0L 250 or 350, no warranty. God only knows why.
Hello /too many toys/👍 Love the video and subscribe to your channel and of course thumbs up 👍👍👍just found your TH-cam channel and because I’m new at this Power stroke 2006’ F350 I love researching on TH-cam comments and videos about my new issue cold start battery light comes on stays on and then goes away as I’m driving
Please if you have any answers or tip for directions? I’m guessing alternator but I’m not sure
Thank you again for all the videos
You're welcome. The first thing you need to do is monitor the voltage. Cold start is a high load situation with the glow plugs being on, so if the alternator has some diode issues or other things, it could be it can't output what it should. You can get the alternator tested for free at auto parts stores, and you should have the batteries tested too. But with that information, don't jump into it yet. The store personnel are not actual mechanics; they are only as good as the training. Sometimes they say something is good or bad when it isn't. The people that frequent forums like Powerstroke.org or FordTruckEnthusiasts can help you through it. I'm on both of those and can help here too. But my review of comments can be once a day or two.
@TooManyToys Question for you: I have continuity at the sense wire but no voltage (key off). Key on I have voltage at the sense wire. Other symptom is a low brightness battery light (it's kinda faint)
Alfio and I had discussed this in PMs on a forum. He had an issue where the wire broke at the eyelet, so when it contacted the broken ends, it measured as though it was OK.
@@toomanytoys Yes, thanks! It didn't make much sense but got it all sorted out. The intermittent connection at the eyelet made that one tough to diagnose, I super appreciate your help.
I have the light on a long time ago but the truck works grates but I don’t know maybe because my truck has 2 alternators
You may have a situation where one of the alternators has a bad diode. All alternators have a slight AC ripple; the diode packs are not perfect. But if one diode malfunctions, the AC voltage ripple will be higher, and the deviation to the battery side of the dash light will cause it to illuminate.
I'm having a big issue. I have a 2005 did the usual, replace the batteries and the alternator and within a few weeks suddenly the battery light came on and with a short period of time the truck was dead, TOTALLY dead, no dome lights, not door locks, totally dead. I got the truck started and had a local auto parts store test the system, it was determined that "new" alternator was bad, so, I put another one on, charged the batteries back up and started the engine. After driving it around for a while I brought it home and parked it. About 2 hours later I went back out and again, totally dead. I took the new batteries in to the parts store for testing. They did a full charge and diagnostic and said they were good. I got a different, slightly bigger (110-135) alternator on it and the same thing. So, now I am at the mercy of hunting for a parasitic draw. My question is that with it draining so quickly, is there a location I should begin looking first?
That's a big drawdown, Keith. Parasitic hunting can be frustrating and take some time.
Two things I would check first. One would be without the engine running to remove the 4ga cable at the passenger battery post (and any other cables you might have added to the alternator positive). When you remove that cable, the Glow Plug Control Module may have faulted and kept the glow plugs on if there is a spark. That is one of the few things that would drawdown two batteries like that. It's happened a few times in the past. You could also leave that cable disconnected overnight to see if the drawdown still occurs.
Secondarily to that, you could disconnect the GPCM connectors only, and if there is still a drawdown or spark, it would relate to an internally shorted alternator, although the chance of multiple alternators having an issue is remote.
The other thing is that while the store checked the batteries, it was right after a charge. You could disconnect both overnight or for 24hrs and see what the resting voltage is if one has an internal short. I have batteries that are disconnected for up to six months, and they still retain 12.6 to 12.7v. One sorted battery will take down both.
If those don't work, we could discuss some other hunting.
@@toomanytoys I found it by accident. It was my glow plug controller. I had removed the passenger side charge pipe to check ground wires underneath. In the process of putting things back together I had reconnected the batteries and last to do was reconnecting the charge pipe. While I was installing it I burned my hand on the controller. I realized that it shouldn’t be hot, I had just reconnected the batteries. Sure enough it was shorting out or something, so I replaced it and all is well now.
@@keithloomis2214 Glad you got it fixed. There are few things that can draw the batteries down that fast!
Does this check work for the earlier 2001 powerstrokes? I have no battery light on the dash and my alternator is not charging my batteries. I can't figure out if I have a harness or gauge issue or just an alternator issue. I'm no mechanic and don't know of a trustworthy shop to diagnose the issue.
It should, but I don't have the diagrams for the 2001 models. The forums on Powerstroke.org or Ford Truck Enthusiasts should have it.
i have a ford e350 starcraft bus and the battery light has never come off since i purchased the vehicle whats the problem
If I get 14 volts out of an alternator, I'm doing great. 13.5-14.0 is normal. Lower if ANY thing is on... Been through 3 alternators and same results.
Need help my battery light don’t come on but but the batteries won’t charge so is it the instrument panel need replaced or what I’ve changed the alternator and have 2 brand new batteries
It could be a fuse, instrument cluster, or wiring to the cluster. I'm showing links to how to diagnose the circuit at the alternator (it's in the video). And how to diagnose the cluster. These are both for 2003, which is the only one I have. Later models may be the same, but I can't confirm that.
drive.google.com/file/d/1sX4GPKKKANTDUoNnaA4LHPcZEbRkdPt-/view?usp=sharing
drive.google.com/file/d/1c0e9qVIg8iNKODZPZcBj3J8GAHl9p7eb/view?usp=sharing
What about high voltage? My battery light comes on , dash, speed, rpms, radio and heat/ac fans off. Ob2 battery reader says 17 volts
That can either be a bad voltage regulator in the alternator or an interruption in the sense wire that goes to the battery, fused with a small fusible link. A bad connection at the two-prong plug at the back of the alternator can do it too.
If the alternator cannot read or "sense" the battery voltage, it can push higher amps to increase the voltage. The "battery," really a voltage differential lamp, will come on if the alternator voltage is lower than the battery voltage, which is the normal operation but just as well come on if the alternator output is higher than the battery voltage.
@@toomanytoys This is the comment I was looking for. Mine 05, didn't have the light on and voltage dropped to no start. Checked alternator and it was bad. New re-built alternator 135 amps. I had charged the batteries while I was changing the alternator. Went for a drive and toward the end of 15 miles, the battery light was coming on and going off. I'm not sure where I'm going next but I'm thinking too low amperage for the rig. I'll go thru your steps and see if anything interesting comes up. Any further comment would be appreciated.
@@pdxbk@pdxbk I would really check out the pair of wires around the plug-in connector. Or replace the connector with a new pigtail, using the pigtail wires to make the harness a little longer.
I would add that today, many of the rebuilds have a lot of issues; I'm to the point where I don't recommend any rebuilds anymore. It's that bad.
I got an 02 excursion with 7.3. Battery light Will come on mostly when you are on the throttle. I did everything in your video, truck runs great, just the light issue. It started after I had the cluster worked on. There is a battery saver relay delay that was causing radio and Windows to not work. The guy didn't fix it, plus now the battery light comes on. I sent the cluster to circuit board medics, so far no more radio and window power issues, but batt light will come on if you are in the throttle. I checked and wiggled the two small wires, both are as expected. Added a big ground wire from at to inner fender, then to neg on batt. Big power wire is good as well. In "test mode" with the cluster, it shows a consistent 14.2 volts, revved up or idling, but batt light Will come on during rev up . Ant other stuff I can check? Thanks for your help!
FredFlintstone21 I’m not an expert on your cluster, but I’d talk to circuit medics again. There could be a diode issue within the alternator that allows alternating current into the DC which I’ve never experienced but understand can be an issue. But first I’d talk to CM then if no resolve get the alternator tested at one of the stores that’s does it for free.
TooManyToys
The local circuit board shop is when it started. Then I was like, ok, I'm sending it to the pros. (Circuit Board medics) and in my typed up form to them I told them about this batt light issue, along with main issue local shop didn't fix. I can swap alternators with my old one. I kept it, and just upgraded to a powermaster. Will be interesting to see if batt light don't come on when hit throttle
FredFlintstone21 with what you’ve gone through swapping would probably be your best way to A-B the problem and find the source.
TooManyToys
I took the dash apart, ran the truck wiggling and checking wires. The only thing that would trigger that battery light coming on was hitting the throttle. So I put my old alternator back in, swapping out the powermaster i had in there. The problem went away. Engine revving no longer produces a battery light on. Yaaaay!
Sometimes you just have to A-B things to sort them out. Glad you found the issue, sounds like a bad diode getting some A-C in the circuit.
whats happening when i have 48 volts at ficm but no injector clatter?
There are two sides to the FICM, the power supply side, and the logic side. The power supply side is what we monitor by the 48v. When the capacitors or other components in those circuits are hurt, you'll get less than 48v. The logic side often does not have a tell, other than not working well - like no chatter.
Mine comes on and goes away when running for a little while
I would first check the two-prong connector at the back of the alternator. Have someone watch the charging light while you move the connector and wires around while the engine is running. If it doesn't change, more likely it's the brushes in the alternator.
I don't mean to ask a mechanic on the internet but I'm at a loss...I have a 03 6.0 with new batteries and alternator and truck will start and run but battery light will be on for about the first 20 minutes where it is draining the battery and then like a light switch everything comes on and system is charging like completely normal. Not looking for a diagnosis knowing how hard it is to do with out seeing the vehicle but maybe somewhere for me to start would be appreciated
I guess when you say not charging you are confirming that with voltage as well as the battery light.
You mention a new alternator. Did you have the exact same situation with the old alternator? If the old one did not do this but just failed, I would suspect the new alternator.
I would double check the connector on the back of the alternator, and even move it around when the engine is running but the alternator is not charging to see if it starts charging with the movement. On mine my connector got funky and I had to splice in a new one. Others have had loose connections there, too.
@@toomanytoys I checked the voltage and hardwired the connection with gator clips and still currently have the same problem my previous alternator failed on me while driving truck died as I was 2 hours from home now currently it will do the scenario I explained and after about 20 minutes the system works fine and has no issue untill I start the truck again
Also don't know of this helps but when I jump start the truck the battery light will stay on also for about 20 minutes even with jumper cables connected the whole time then like a light switch everything goes normal.
@@mickkeating4400
But while your previous alternator failed, did it have the 20 minute delay?
Even if jumped, if the alternator is not outputting, the light will be on since it shows if the alternator is charging. You need to back probe the connector to see if the LG/RD wire has positive voltage with key on - it doesn't have to be running. That is the trigger signal through the battery light which turns on the alternator. If that does not have 12v then it's before the alternator and in the gauge assembly. If the back probe shows voltage, then either the connection is bad or the alternator is bad. I'm leaning towards the new alternator, the regulator actually.
@@toomanytoys it did not have the 20 minute delay with the old alternator and when the new one was installed it worked fine for about two weeks then it started so I put new batteries in it and tried that and it didn't work I'll check the check connection tomorrow and I apprtall the help thank you so much
What if my control green wire sporadically has full power sometimes and then only 1.7v other times? Would that be the alternator? The charging output is always a full 14v. It’s whenever the control wire has the 1.7 V that the battery light comes on but my alternator will still be charging my batteries
That's a tough one, it could be within the alternator but still could be from the control side. That will take more then a parts store bench check to sort out, more towards a specialized automotive electrical shop than a parts changer.
TooManyToys When the light is on if I takeoff the wire it has a little over 12 V when I put it back on the alternator I’m seeing that 1.7. That makes me think it’s inside the alternator. Also I think that you did a nice job on your video
TooManyToys I changed the alternator and that was the problem. The control side had some weird issue but allowed voltage output to remain the same.
I tested everything and it still comes on randomly and goes away
Did you wiggle the connector around while it is running to see if that changes anything?
Hmmm I ran though this and got all good numbers, but my battery light is still on?? I am guessing that means alternator even though it shows good voltage? I didnt load test battery or alt, kinda far out of the city for that.. but the voltages all are good. Also the battery light glows BRIGHTER when you rev it up... about 13.6 at 1200 RPM.
I had responded, but it's not here.
If you are taking the voltage at the batteries or alternator, a voltage of 13.6 rev'd without accessories on is still low unless the underhood temps are really high. it should be 13.8 to 14.2.
A lower voltage or the dash light remaining on can be a bad diode in the alternator. To check that you need to install your voltmeter again across the battery terminals or the alternator output post and the case like you were checking for voltage. Except put the meter into AC reading mode. Running and especially with a load like the blower fan on high ideally should have a reading of around 0.25v, but some can read up to 0.50v. Higher then that would indicate a bad diode.
@@toomanytoys AH I see thank you for that explanation... either way I guess its the Alternator... I will replace it tonight and see what happens. All the wiring and such seems in good condition... Thank you again for such a detailed step by step video!!
@@toomanytoys I replaced it now I get 14.1 at idle.. much better... but it seems to get fairly hot...the temp gun says around 175... is that normal? the batteries wernt discharged before hand...
I don't have a good database on how hot the different alternators get on these trucks. Of course, they will get up to underhood temps, which can be really high. My 230 amp unit with 2 internal fans during summer running would be a 130F, but normal driving is only around 20 amps once the batteries are mostly charged (10 min) so it's a cake walk for it. Others have mentioned being over 160F. At this point, it would be hard to say if it's abnormal. If there is a hurt cell in one batt, it will task the alternator always. IF the truck is DOA in the morning, that would mean a shorted winding in the alternator and the reason for the heat. Anytime you can get to an Advance, Autozone, etc they will test each battery, just do it as I did in the video, one at a time. It can be a drive up rather than bring them in. If the batteries are less than an ideal charge, that new alternator will try like hell to get them up.
@@toomanytoys Good idea I will get them tested asap. Thank you again for these videos!!
When testing the alt pig tail, where do you connect the neg on the multimeter? I am getting 0.00 when connecting to the neg post and the positive to the Orange Blue alt wire. Any ideas? Thanks!
For testing both circuits to the pigtail, the negative lead is connected to the battery negative. The Orange/Light Blue lead should always have 12v. If not, the 20ga fusible link may have been compromised. But first make sure your multimeter reads 12v when the positive is connected to the battery positive or the alternator positive post.
TooManyToys awesome thank you for the reply! Do you have a part number for the fuse link?
Also note, I am dealing with a 7.3 not a 6.0. Using this vid as reference.
The fusible link is part of the entire engine harness, so it's an expensive item to change. The in-field service by techs is to cut out the 18-20ga fusible link and install a replacement. So you really need to be sure it's not 12v with continuity before you start cutting.
The circuit you are identifying is the "Sense" circuit, telling the regulator what the battery voltage is. The typical failure of the loss of this circuit is an alternator that is not regulated in voltage, going higher then 14.4v. If you have no charging, it's typically not this circuit, although the fusible link can be burned.
Another field replacement is to install a replacement fusible line (18-20ga) splice into the Og/LB wire coming out of the connector and putting a terminal on the other end of the fusible link that can be bolted under the alternator output post. It does the same as the original circuit and other brands of vehicles do this internally within the regulator.
I am getting ~0.01v on the orange/blue wire with the mulimeter set to V 20, is that normal or should it read ~12v?
Batt good alt charging at 14.1 (full load ac blower and all dipped to 12.6) what else could be wrong?
Dropping lower to that level with all the accessories on is typical of trucks with the 110 amp alternator. At idle it puts out 60 amps (110 at higher driving rpm) but a pickups full electronics on draws 70+ amps, an Excursion more with its added items. So I’f your drawing 70 and supplying 60 from the alternator, all it can do, the voltage will drop to the setting battery voltage. You need a fair amount of headroom with higher alternator capability so the voltage stays higher. It’s why many opt to install a 140 amp alternator or higher if they are concerned about lower voltage and FICM health.
With dual alternators, the battery light stays on briefly because one alternator is shut off to keep from overpowering the glow plugs. This is normal.
While with a dual alternator system one alternator is kept off during initial glow plug time to prevent kicking off the GPCM, if you have the battery light on during the initial start time it means the primary alternator isn't working. The light should never be on with the engine running. Many dual alternator owners end up finding when they have the light all the time that both alternators need to be replaced, they just lived off the one good one.
I have a f350 I put a 700 CCA and then there's the original one it's a 850 once and a awhile it won't start in morning I have a Chevy van too jump start it then it runs all day for a few days
Sorry, I never saw your post. I'm sure by now you would have had the batteries tested for CCA.