In a previous video I had a look at a customers F250 that was stalling out on him. Our testing lead us to the start run relay. About a month later the truck shows back up at my shop with the same symptom and guess what! The same row of fuses had no power in the fuse box. Oh boy....
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We're in trouble now folks. We fix this. F250 fixed it quora quote. Then about a month and now I got jenked in on a flatbed.

The guy says it's still doing the same thing that it was doing. Of course battery's dead so let's drag out a charger action here and there. couple hours drawn full nuclear so we're gonna nuke that thing for a little while. Get some turds back in a bag quick over and see what's going on according to the fellow and I spoke with him before he took it.

Here is is it was doing the same thing. You know it's like to light up, you know it sounds like no communication. He said he was going to change some relays and do some stuff under the hood. So I don't know what he's done.

um I was pretty definitive with our diet last time. if I remember it was the Run start relay or something along those lines and we're losing power to a group of fuses. so we're going to look and see. perhaps we just got a crap part.

I Can't doubt it, but um, you know, maybe. oh first really went bad. If this really went bad, that would be kind of weird. but we're gonna check that row of fuses providing it doesn't start and see.

You know, do we have the same thing where I start right with our same diag and then kind of turn it backwards? You know, did we just serve a connection by freaking around in there I Don't know. We're gonna find out before we at least we had a click. Now we got nothing. Let's go see if that fuse is dead under the hood.

Teslie it works I think it was this whole row of fuses here. Yeah, those are all dead. Yeah, it was this throw here if I remember correctly. All right, so that's pretty interesting.

Would we miss here? Phyllis there's our relay. Let me look down inside that box. This was kind of weird I went out I see our uh, charging voltage was a little high here on the scan tool and because we had the battery charger on a 40 amp right there while it was charging I didn't leave it on nuclear I just do that. It'd be funny for you guys.

but um, we had a charging at 40 amps and I see the charging bolts of the world high. So I went up to shut the charger off. oh hold on a minute here. close here folks like I say well check the charger off and put it down on a two amp setting and then all of a sudden I hear everything light up in the truck.

You also like oh, it should start and it started insert so we got it inside I'm just out of curiosity so perhaps was I creating a problem having uh, too high a battery voltage? Well, I've never seen that before. Um, maybe we just got lucky. Maybe it's a terminal fitment issue down in there. Okay I Got a few questions for myself at this point.

Let's go see what's up. We'll make sure the key's on. so I guess we're going to kind of disregard that for a moment. I don't want to sit here and keep nuking it.

Um, the volt meter on the alltels are anywhere from a half to eight tenths of a volt off. Maybe it's just a big old coincidence, but it sure seemed I mean it was like the second I clicked it from 40 amp down to 2 Amp So maybe coincidence, but kind of interesting I did take so you know we hear the clicking going on over there. you can see I took that terminal and I tweaked it just a little bit and then when I stuck that in I did get you know this whole row of fuses to light back up. This is our Run start relay.
of course you know we're causing all kinds of issues in there pulling that in. Now let me find my test light and check and see. I guess we have this. It's this row of fuses, right? I haven't looked at any diagram I'm just trying to pull it off memory I haven't even edited the video that we made a month ago, not sometime back in February I think it was now.

we're actually I think it was a month ago to the date because I looked when he called. it's February 23rd when we did the first one and I think it's March 23rd today or March 24th. So yep. so now these these are all dead.

foreign. Kind of foolish here. but let's just see. Okay, so we have power.

Oh, this is interesting. I'm not losing it here. So this is a one of the powers for the load side. Okay, but on the control side of this relay I mean one of these legs should have power, one should have ground and I only have power on the load side? That's that's very interesting.

Okay, we would. We would have checked this last time. we would have checked I know for certain if we had if we were missing power or control. Okay, so maybe I'm just barking up the wrong tree by uh by tweaking on this.

Okay I always think of maybe pin fitment issue or something, but I would have thought we would have checked that last time I can't remember for sure, but it appears that we're missing power on one of the control sides here. load side you got big terminals. We got power on one of them of course. then when it relay turns on it, you know, jumpers through.

but I say at this point we get a diagram. see maybe by taking that in and out, maybe something inadvertently turns off. but you know who controls this. uh, relay.

Let's find that out. I'm curious. just a second. Yeah, so right now I have no control of my windows either.

and I'm assuming if we stick this back in, make sure you guys are in a safe spot. I think you're safe I assume we have a no start. Okay, yeah, so we have a no started again. we're kind of back to where we were outside, but thankfully we're inside so that's good.

Hallelujah And we've also discovered it appears that we have no power on the control sign. Okay, so I think it's a different you know, similar symptom, different problem with more symptoms AKA like none of the windows and none of that crap work. but I yeah I'm pretty sure last time they did semi-observant I thought I would notice that hang out. Let's get let's get cranking.

We'll hook my uh before I hook up that wiring diagram I've got this brand new tool I've never even used it yet. I Just literally just got it. Uh, it's the AES wave you activate and it's A. It allows us to do relay testing outside of the box.
so if we're up to ground here, this is going to allow us to manually activate the relay that was there so we have no power there, but we should be able to turn this on. Okay, and we can. We can feed power you know, simulate turn the relay on and off, but it allows us. It's kind of neat, gets itself out of the box, and it's got a current loop on here if you want to measure current flowing through 30 and 87 or 30 and 87a and then it allows us to measure the control side too 85 and 86.

So on a relay, typically number 30, Pin 30 is your full-time power. It's going to be the the load for it's going to be the power for the load side of the relay. So you know when it's Maxi fuses it goes into Pin 30. and if it's a five pin relay, you're gonna have Pin 87 which is going to be when the relay is activated and Pin 87a when the relay is, you know, turned off.

That's which way the power flow goes. So when we flick this on, we send power from Pin 30 to Pin 87. light this up. Okay, when the relay is functioning normally, pin 85 or 86, one of those two is going to have power I Don't know if there's any standardization to that or not, but I've seen it both ways.

One's going to have power and one's going to be groundside switch in this case. So let's see if we have our ground site control. Let's just find out what all we're missing. So I'm going to hook my test light to a power source here.

Yeah, be careful with this because you don't want your vice grips to fall over into something. Let's see. Okay, we have ground so let's just try Pin 85. Okay, our test light lights up so that should come on and off with the key.

I'm assuming because that should be our control wire because the other one here. Yeah, so that's going to be our control. So if I shut the key off, I'm assuming that's going to go off and it does. so.

Key on! Dr P9 So our relay is receiving control. However, we are missing power on the control side so we're back to where we started. But I just wanted to show you that tool that way there you guys can see what kind of testing we're doing outside of the relay box. We're missing power here and we need to see where that comes from.

We can certainly jumper power to this being unfamiliar with the tool I Don't know if that's a great idea I Can't see why it wouldn't be I Just thinking out loud here. Um, but before we do that, let's grab a wiring diagram and see where is that power for the control side supposed to come from and is that related to any of the other issues that we're having? I'm assuming it is wiring diagram sets Fuse number 45 So let's look in here. Let me just get this oriented correctly so we're not. Ford Fuse boxes can be kind of confusing sometimes.
Let me just figure this out. I Think it goes this way. Okay, yeah, because we put a little white paint marker on there for that relay. Okay, so Cues 45 is supposed to be this one right here.

47 46 45 Let's see if it has power on it. Our test light still works. Oh, and it does Okay, let me make sure I'm under eight. Fuse 45 Yeah, so we've got this relay.

Well, that's curious, isn't it? Um, because that has power I Want to make sure that I'm in this thing the right way? Yeah, we are. Okay, so all right. Well, let me double check my wiring diagram. but uh, if this is the case, we should have power here and we don't.

I'm gonna double check my wire diagram, but if that's the case, then the problem's in the bottom of the fuse box. It would have to be. There's got to be a loop of wire because I think Fuse 45. Let's go look on a diagram because that's the Run start relay this brown with violet.

We know this one works because this is a control side that's the ground side of the relay. This is what we're missing right here. Bring it down around town. Fuse 45.

Why would fuse 45 be a 10 amp fuse and all it does is run the control side of a relay. Um, I mean that would need to be like a one amp circuit because this really is insignificant. It's nothing. so that's weird.

I We have to follow the facts. I'm going to double check an Oem diagram to be sure, but according to this, we have a broken wire between here and here. or the other thing we could have is just crappy pin fitment and Infuse number 45. let me set you down.

Uh, which one was 45 Again, this one you see, our fuse is good, but yeah, well, it looks pretty dang nice from up here. Yeah I don't see anything? I don't see any weird Monkey Business Let's go I'll just wiggle this fuse just for pooping laughter here. Yeah, yeah, that's got to be broke under the box. Let me double check an Oem diagram.

Well, we might be opening Pandora's Box here, but I think give it the old cows. try. Follow the facts baby. Um.

I've unhooked the battery not super familiar with Fords I Don't know if we have enough room if we unhook the battery cable going to this, if we're going to have enough room to flip it up and do what we have to do. Uh, so I'm not real sure, but let's uh, grab something I guess grab nothing. I Was gonna grab a screwdriver, but it looks like the tabs kind of pop up down there. almost here.

Yep. I think I'm gonna have to unhook the battery cable here passively. Okay I can't really tell, um, tell you what. It's not keeping you guys here in suspense I'm going to fiddle with this thing for a while to see how how we can gain access to whatever we need to gain access to.

I Don't really know, um, it just feels kind of tight I see how the wires come into it here? but I don't really quite understand how it comes apart quite yet, so let me fiddle with that. It looks like maybe I could take the bottom case off. I'm gonna hook the battery cable because that might be holding us and then I'll come get you guys once. I Kind of get some things figured.
I'll explain to you what's up. Tell you what boys. The most unreliable, least longest lasting truck on the road. But God dang, they don't do stuff that's freaking stupid.

Um, this is just assining folks. this is all one piece of the entire harness. It's non-repairable, non-serviceable item. What a stupid freaking design even.

Chrysler knows this. but I tell you what, you can get it out. Get it this far top of the morning to you motherly lover dude that pissed me off. Latches on the back of this box way up under the firewall I Don't know what you're supposed to do I Took the air box out of the way, but give me a break.

Break me off a piece of your KitKat bar. I'd like to find that engineer that freaking made this thing. What's married with a good old connector dude? Oh look at that that's been quit piss and moaning pink. There's a broken wire staring us right in the face.

Or at least a broken wire. Let's see where's it run to on the reviews gray with the red stripe? I'm pretty sure I remember that from the diagram nobody's ever been in here. Everything that taped up there was no tabs broken. So this is a Hokey Pokey right from the factory defect in The Wire Um, Fortunately, there's enough wires sticking out there.

We should be able to get a crimp and seal connector on it. Maybe maybe. let me go get a pair of wire strippers and I Just tell you what stuff like this makes me hate my job. Calm down.

So what? I'm wondering. Well, first of all, this is. let's admit this is super bizarre because I'm gonna have to go back and watch the first video I mean I know I lived that moment but I don't recall right offhand. There's no way I misdiagnosed this the first time and was losing power on I don't know Maybe I did maybe I'm an idiot I I would have checked I know I would have checked for power on the control side I Don't know Maybe I won't publish any of these videos.

They're both stripping before anybody asked. Uh, these are the snap I call them the Hammerhead strippers allowed to get in there straight. That's part number from Snap-on Maybe this is all my fault. Maybe I should just give up not be a mechanic anymore.

I'm thinking we're gonna have to solder this one because I'm not so sure I Got these wires stretched so freaking tight right now I Don't know if I can get in here and do what I got to do with the crimper I know I can solder them, but let's see if we can get in there. get her crimped off. we'll be good I have to charge over there on two amps. but I know it sounds like ridiculously loud and the camera I'm gonna slide that baby down on there.

Let's see if we can't get in here to give it a proper crimp. I think I totally missed. Oh I didn't feel like a real idiot if I misdiagnosis because what are the odds? really? out of the hundreds of circuits on the car to have the same circuit had the similar problem or the same problem I think the no crank portion of it there, uh, must have been just a strong coincidence where there's two issues That seems kind of bizarre. That's still in my mind.
this thing's still in my mind. Let me go get something to heat that up with a little. Saturday It's got a little heater tip on it here so we can heat this up without melting everything else in the Box All right, she's all melted and solidified. This thing will probably go back together easier.

It came apart, but there's about three zip ties that are not getting put back and they're one of them's way down here on this lower plastic tree where the harness comes up. they're all zip tied one up here. I Might put back, but this harness is all zip tied to all the plastic because it's supposed to be. You take this out and you throw this whole thing away and replace the wiring harness is how it's supposed to be done.

But one thing we have to be cautious of and I have to be cautious of this is the wires here to make sure that they're when. I click it back onto the bottom half of this tray that they're not going to get pinched. So I'm going to work on that I'm gonna do it off camera. then I'm going to swear it a little bit and uh, I don't want to do that on the YouTube So let me, uh, get after this thing.

we got a fish back down in there. put that relay back in. Flow through. it should start just fine now.

Thank you. Let's get the girls. got no exhaust on it inside here. Oh what do we do with the lid for that thing? Give it flying lessons.

Oh no, here it is. let's stick this back on there. I Was able to get that bottom all back in and click down. It's just a pisser because I mean everything is just so tight.

You know there's no, uh, no room back in there to do anything. Probably if you took the brake booster out it'd give you a little more room. Flip it around, but why don't this lid want to go on now? I'm curious to know if I misdiagnose it the first time or it was just a situation like the whole battery charger deal. You know every time we checked it, everything was there that we needed I don't know, you've been driving it for a while so whatever, it's fixed now I'm done.

We're done. Thanks for watching foreign.

98 thoughts on “Intermittent stalling ford f-250 : the real fix”
  1. Avataaar/Circle Created with python_avatars Bill Koskie says:

    ford = crap wiring

  2. Avataaar/Circle Created with python_avatars R S says:

    So you are human after all. I still can't get my gas gauge to work properly or at all on my double nickel and I ran out of gas last Sunday. I performed all the tests YouTube had to offer. Everything works fine when the fuel sending unit is not installed but stops working when I install it in the tank. I've tried installing a separate ground wire but it still does not function maybe the signal wire is grounded

  3. Avataaar/Circle Created with python_avatars Glenn Hamblin says:

    As for the 10 amp fuse. Fuses are specified to protect the wire, not the load. I don't know what gauge the wire is. But, my guess is 10 Amps is the limit for that wire.

  4. Avataaar/Circle Created with python_avatars DatsNotABlazah says:

    No room for the fused power distribution center due to All that big Ole ford mota

  5. Avataaar/Circle Created with python_avatars Carl Golden says:

    As much as you may doubt your self. I wish I was closer to have you as my mechanic.

  6. Avataaar/Circle Created with python_avatars Lynn Miller says:

    Eric working on vehicles come with a price. It is just part of the business.

  7. Avataaar/Circle Created with python_avatars Nelson Narciso says:

    Don't be so hard on yourself you still performed a great diagnosis and I'm sure you worked it out with customer to make it all good. Great video. We all get these.

  8. Avataaar/Circle Created with python_avatars blucollarron says:

    No young fella , don't dis yourself , I'm 15 years into this longer than you and you know 10 x than I ever will . Thanks for what you do .

  9. Avataaar/Circle Created with python_avatars Ghauster says:

    Ah Ford. They are trying to beat others to the title of worse design decisions ever.

  10. Avataaar/Circle Created with python_avatars Rick Martin says:

    Eric there isn’t a perfect human being on earth, the fuse box wasn’t bad you saved the customer 100s of dollars, ford should be slapped for designing a fuse box with no wire connectors, go easy on your self brother , you always diagnose the problem 99% percent of the time those are very good odds, you have always done fantastic work, always love your videos

  11. Avataaar/Circle Created with python_avatars Graystone Husky says:

    If only engineers had to fix their own creations… Laughs

  12. Avataaar/Circle Created with python_avatars DouglasH says:

    Hi Eric and the lovely Mrs. O., Well well, so you are human. In the last video you tried a relay and said let him run it and see what happens, well looks like you didn't misdiagnose anything. You said first thing it's probably in the fuse box. You deserve more credit than you give yourself, but I guess that's why all these shops send you their problems because you're the best and humble. Great job buddy!!

  13. Avataaar/Circle Created with python_avatars Gary Pollack says:

    I gotta get me those hammer head strippers. Thanks

  14. Avataaar/Circle Created with python_avatars Pinoi_Cowboi says:

    I feelya…Mama said there would be days like this..!!

  15. Avataaar/Circle Created with python_avatars Luis Marty says:

    Thank you, Eric. Nobody's perfect. You still are the man.

  16. Avataaar/Circle Created with python_avatars springfield45 says:

    Actually its something that everyone should see – parts 1 and 2, intermittant problems happen and you cant really tell if its 'fixed'. Even now after repairing the wire, hey the alternator could be going wonky sometimes and screwing something up too (ok not, but you get my point).

  17. Avataaar/Circle Created with python_avatars HouseCallAutoRepair says:

    Same wire, next connector in line… green crusties…. back again in two more weeks…. It loves your tender words!

  18. Avataaar/Circle Created with python_avatars xoxo2008oxox says:

    But FoMoCo saved BILLIONS by leaving out a multipin connector to the master fuse box! Think of the weight savings! Why make it easy to replace when stealerships can bill for it! Don't knock yourself for the management's over-ruling of design engineers logic. PS. Don't beat yerself up over a repeat repair. I know the feeling, the "panic" of was it something I missed? Or worse? And the customer paid. I have a duty to them, as I honor my work. Just had this happen to me today. Helped an older client with her computer problems. Then I get email next day from her phone that "nothing works! Computer, keyboard, nothing turning on!". Well, I rush over after my day job, and find, she unplugged the keyboard, and turned off the mouse. The computer was asleep so hitting the space bar wouldn't wake it because…the keyboard she unplugged. Now I realize, I swapped out her cordless keyboard for corded, but she misunderstood it was not a cord to "charge" it. And the mouse was turned off. (Apple, like Ford, has dumb design with their Magic Mouse as you can't use it at all while it charges. Atleast Logitech has better mice!"

  19. Avataaar/Circle Created with python_avatars Robert Wheatley says:

    That's what you get when you buy a ford

  20. Avataaar/Circle Created with python_avatars Hola! Craig Goodwin says:

    Eric, thanks for the follow-up video. Sometimes it just takes a second look to finally nail down the problem. Thanks for Sharing!

  21. Avataaar/Circle Created with python_avatars rbspider says:

    I recall you checking that power and there was power on both sides. The problem was it stopped failing after you pulled that relay. You went with a new relay and wasn't 100% sure it was fixed but it stopped failing , not much you could do. You even took the relay apart, it looked good.

  22. Avataaar/Circle Created with python_avatars Chris Laccitiello says:

    You sound like me. Sometimes being a mechanic is the loneliest thing to be.

  23. Avataaar/Circle Created with python_avatars mlsargent51 says:

    I had a day and job just like this today, but a toyota. PITA to get it up and apart enough to test. I feel your pain! The fact the truck came back with the same symptoms, and you still made and posted a video, shows the quality of your character. To be admired for sure.

  24. Avataaar/Circle Created with python_avatars Paul1958R says:

    Opening Pandora's fuse box! Great video – thank you!
    Paul (in MA)

  25. Avataaar/Circle Created with python_avatars 0313bouchey says:

    Great video Eric!

  26. Avataaar/Circle Created with python_avatars johnnyq1233 says:

    Chances are that the relay did have an issue as well as that wire being wonky too!!! If I remember correctly you had a scope on both hots on the relay. What are the odds of having 2 different issues with the same circuit?

  27. Avataaar/Circle Created with python_avatars Kennard Johnson says:

    Smoke a Dobie and it will be good

  28. Avataaar/Circle Created with python_avatars Prestia2011 says:

    Are you doing ok Eric? Seems like there is something going on with your mouth/speech?

  29. Avataaar/Circle Created with python_avatars Doug Hahn says:

    The fact that this fella brought his truck back to you says a lot about the trust he has for you. I wish I could find a mechanic that I could trust 1/2 as much in my area. We all miss things from time to time. However, without trust you never get a second chance.

  30. Avataaar/Circle Created with python_avatars Iain Kinsella says:

    Phase 4

  31. Avataaar/Circle Created with python_avatars Abrams mobile auto repair says:

    At the end of the day, at least you stand behind your work and revisit it when necessary. That speaks volumes for the type of man you are. If the biggest mistake you made was missing a broken wire, i would say you are doing better than some of the shenanigans i have had to check out.

  32. Avataaar/Circle Created with python_avatars Kennard Johnson says:

    You had power last video

  33. Avataaar/Circle Created with python_avatars William Von Roenn says:

    Heaven forbid they leave some slack. But I guess since it is not serviceable it doesn't need any slack… Lol. I will stick to my 2004 2V 5.4.

  34. Avataaar/Circle Created with python_avatars Kennard Johnson says:

    It happens doc

  35. Avataaar/Circle Created with python_avatars Bruce Bratschi says:

    Built like a YUGO at 4 times the price. Hilarious

  36. Avataaar/Circle Created with python_avatars DavidKupy says:

    Uh Oh… I felt a tremor in the Force coming from Avoca.

  37. Avataaar/Circle Created with python_avatars Live Wire says:

    "I'm going to swear a little" Eric you have the Patience of a Micro Surgeon! 😎 Salt Sucks I love Tennessee!

  38. Avataaar/Circle Created with python_avatars Drives11 says:

    Say what you will about that fuse box, I'd way rather have that style than one with a PCB. I can fix a corroded terminal or broken wire, I can't fix a faulty TIPM.

  39. Avataaar/Circle Created with python_avatars Jason Barker says:

    I enjoy your videos. Great diagnostics and detailing poor design choices by manufactures

  40. Avataaar/Circle Created with python_avatars Puder McGavin says:

    I warned you it needed a harness

  41. Avataaar/Circle Created with python_avatars Shade Tree Mech says:

    Intermittent problems like that have caused commercial airliners to crash. In the end they said it was a cracked solder joint in an avionics/black box.

  42. Avataaar/Circle Created with python_avatars E P says:

    Eric O you only human. Your still maverick of mechanics!

  43. Avataaar/Circle Created with python_avatars Alisa Beheler says:

    Quit beating yourself up. You are a great mechanic and I would bring my vehicle to you if I lived in the area

  44. Avataaar/Circle Created with python_avatars Roy Matthews says:

    What? No skin was removed?

  45. Avataaar/Circle Created with python_avatars Hot Rod 1949 says:

    call Scotty Kilmer 😅

  46. Avataaar/Circle Created with python_avatars Meltiah Nye says:

    Eric, have you ever actually heard back from a GM engineer, or one of the other companies? They would probably blame the accountants…
    PS, in the Navy we learned "When tools fail, use harsh words."

  47. Avataaar/Circle Created with python_avatars a g says:

    Please don't let some moronic Ford Automotive Engineer's design that makes trying to fix anything ruin your day. I've recently noted some videos on late model Ford F-Truck Diesels where they need to unbolt the entire CAB and lift it to do some repairs on the backside of the 6.7 Liter Diesel motor i.e. the upper and lower Oil Pans gasket replacement like REALLY? And Ford's attitude is "once it gets out of warranty it's no longer Ford's problem"….like REALLY? Eric – you are a pro beyond pros and heads above anything Ford employs or designs. Now you know, the next time one of these rolls in with the same problem, you can either fix it pdq or send it to a Ford Dealer and let it drive one of their mechanic guys into therapy…