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224: Ford Fiesta No Start Challenge
224: Ford Fiesta No Start Challenge
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About this episode
A challenging no-start issue on a 2014 Ford Fiesta leads to a deep dive into diagnostic techniques, focusing on starter engagement and control module signals. Despite initial assumptions about voltage and starter relay faults, the root cause was traced to a severe voltage drop on the transmission ground cable, affecting the transmission control module's park/neutral signal and causing the ECM to release the starter relay. The episode highlights the complexity of modern diagnostics, the importance of thorough voltage drop testing, and lessons learned from real-world troubleshooting.
Topics:
ford fiesta no start
starter relay diagnosis
voltage drop issues
transmission control module
park neutral switch
ground cable problems
module communication
diagnostic process
real world troubleshooting
automotive electrical systems
Cars:
Ford Fiesta Active
Today on the show I'll share a case study on a 2014 Ford Fiesta that engages and releases the starter when cranking, but will crank over if the starter relay is jumped. We made a wrong call on this one at first, but eventually get to the root of the problem.
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Ford Fiesta
"...e set you up on the scenario here. This is a 2014 Ford Fiesta with a 1.6 liter."
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Welcome to the Automotive Diagnostic Podcast.
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Hey, what's going on?
Automotive World.
Welcome to another episode of the Automotive Diagnostic Podcast.
My name is Sean Tipping and I'll be your host.
Once again for today's episode.
I've got another case study for you, so thanks for joining me.
Sit back, relax and we'll get into this one.
I'm going to continue with my theme go for this as long as possible, and I don't think it'll be that hard of talking about cars that kind of get beat up on and struggle with.
This one was no exception.
We made the wrong call on this one initially and we did make it right, but it was a struggle.
It was battle of beat us up, and that's why I'm sharing it.
So let me set you up on the scenario here.
This is a 2014 Ford Fiesta with a 1.6
liter.
This was at one of the shops we service and we were initially called in for what they called a no crank and obviously no start.
I don't know why we call them no crank, no start.
It's a no crank, of course it doesn't start.
They did say the starter would sometimes engage or engage a little bit.
They weren't really sure.
But this thing won't start and it doesn't seem to want a crank.
They already put a starter in it.
They already put a battery in it.
They cleaned up the battery cables.
They're not quite sure what's going on with this one.
They don't have any codes to go with and they don't have any direction.
So okay, we'll come in and check this one out.
Now.
I was actually on vacation when we got called on this one, and so my employee ran out there to check this one out, and most of the time on a no crank, I'd say it's fairly straightforward and fairly easy to figure out what's going on.
Okay, the starter's not activating.
Why not?
Because preventing the starter from activating shouldn't be too terribly difficult.
But again, that's why I'm talking about this one on here.
So what he ended up finding when he got to this vehicle is that the starter would engage on this one, but it would only do so very briefly.
You would hear the starter solenoid close its contacts and you'd actually hear the starter engage, meaning that the drive gear is moving out and engaging the flex plate, but that's about it, and then it would release.
So it's not even turning over the motor, it's just it kind of a loud click and you could actually you could see the engine move just a hair right.
You see that movement in the engine when the starter engages the flex plate, but it wasn't cranking and it would release immediately, right, and so you hit the key, it does that little click and then it releases the starter.
And so that's what they were after, of course.
Okay, so it's not a complete no crank, right, we're getting a signal to the starter, but it's releasing for some reason or another.
Okay, cool, so we should be able to figure this out right.
And I'm walking you through the process that my employee took when he initially looked at it.
Of course we're checking things like battery, like battery connections, obviously, you know, does the starter work itself?
The basics.
When you have a situation like this and immediately this kind of struck Steve as a voltage issue, as it would many of us, right, is there just not enough voltage in the system?
Is there voltage drop somewhere in the cables?
Is there something wrong with the starter, something like that?
Right, it's like it's engaging but then releasing.
So does his basic checks right to make sure that the batteries up to snuff?
We have a jump pack on there checking cables from what we can tell up under the hood, and everything looks fine there.
So one of the things he wanted to try was I'm just going to jump the starter manually at the relay point and see what it does.
And again, this is a test.
I would have done the test many of us would have done in this point.
Obviously you can go down to the starter, but I just want to see, can I try and jump the starter at the relay and what happens?
Is it the same thing?
Because if it's the same thing, well, okay, I'm going to head towards the starter.
If it's not, then I'm going to look at the control side of this relay.
Right, and I guess in my head and Steve's head, is the starter being released because we have some type of voltage issue or is it a commanded release by whatever circuitry controls a starter relay?
And that's kind of the direction that we want to go.
So again, pulls out the starter relay and jumps the two terminals that are the load side for that relay, that feed the cell right for the starter.
When he does that, the engine Cranks over normally, right, the starter engages and it does not release and you can watch the engine turn over and turn over, and turn over.
And I Think you found out, if you put the key in the forward position and do this, you can actually get it to start and run.
Okay, and this will happen every single time.
So now we know we're either dealing with, well, maybe a starter relay issue, but either that or it's on the control side of this relay, because you put the relay back in and does the same thing, just goes Clunk, and then it releases the starter.
So he does his checks to figure out okay, and swapping the relay is the first thing that he did and that didn't change anything.
So then the next thing that he's gonna look at is the circuitry that controls the starter relay, right, the control side of the coil to activate that relay.
What's going on there, and are we Losing something on that side that's causing the starter to release?
Because it sure seems, though, right, and we're not concerned about the voltage of starter, we're not concerned about the ground going to the starter, any of that stuff, because we can jump this thing and it cranks normally.
So, looking at the diagram, both of the control wires for the starter relay go right to our engine control module on this one and so controls both power and ground, and I think one was constant.
The other one was switched, I'm pretty sure on that.
I don't recall which one was, which doesn't really matter for this.
They both go to the ECM and Obviously when you hit the key and you've got it in the correct gear, this thing should crank over until you release the key or the engine starts and swap in the relay didn't make a difference.
So when we're looking at the control side of this relay, what he ended up finding out was that the ECM was Releasing the starter relay.
Right, it was turning off.
Again I should look this up to see which one switched.
But would ever switched Power ground?
It was to the relay, it would just release it.
Right, it would initially apply it and that's when you heard the starter engage, but then it would go away and the starter would release.
So this is a commanded release of the starter.
Maybe commanded is the wrong term to use there, but the ECM is releasing it.
Okay.
So we need to figure out why, and we're start looking at data pits.
And he had done an initial scan on this and didn't have any codes that seemed relevant to this issue.
Checked it again didn't see any codes that were relevant to this issue Right, codes and other modules, but nothing in the ECM.
But we can look at some scan data to try to help us figure out.
You know what is causing this, and the basic ones are going to be things like well, number one does the ECM recognize that the transmission is then the correct gear?
Right, that's something that could stop it from happening.
But also, communication with the module right, the module could be dropping offline the ignition switch input, right?
How does the PCM Recognize that we're trying to crank the engine over?
Is that something, potentially an anti theft?
But Actually don't think that an anti theft would be even really something to look at here.
I Don't know that an anti theft issue would Cause a starter to release after it had already been engaged, so that's not really something.
But I mean, with those are the kind of data pits that we can take a look at just to see what.
What's happening here and, as far as he could tell, on all the data pits you know, voltage to the module, key position, park, neutral position, all that stuff, it seemed to be Okay, even when the ECM would release the starter relay.
And he went back and forth with this quite a bit to really look at it and he didn't see anything and there's no codes and it's for sure, the ECM releasing.
He even went to the ECM on those two wires that go to the control side of the starter relay and it's the same thing right at the module and he could actually crank the engine over Using those control wires At the ECM.
Right, if you send power and ground, the starter relay activates and the thing just continues to crank when you do it there.
So right, all of that is good, the control side of the relay, the relay itself, the load side of the relay, the starter, all all that's functional.
But for whatever reason, again the ECM's deciding to release this starter relay.
And he called me on this and I was out of town and I tried to help him out the best that I could.
Right.
My, my girlfriend wasn't too happy, you know.
We went down and we stayed on the beach and she's like you're working again, but you know I feel really badly than my guys hanging.
I told him hey, you got a question on something, just give me a ring, I will offer you my best advice.
And so I'm down there on the beach trying to, you know, look through some service info and say, yeah, let's see what can we look at here.
And I told him some data pins like, okay, check the starter command relay, check the park position, this, and that that's really all I can think of off top my head.
Nothing rings a bell as far as a Problem like this that I've seen in the past.
There's, there's no hits on identifix.
You know, just double-check everything that you've tested so far.
And right, I'm not there.
So I a lot of the detail I'm giving you right now is, you know, after we've been through it.
But he tried to fill me in the best that he could and I was like well, he just, you got to have these inputs in order for the ECM to crank and if any of those are, basically, we address it.
If not, let's start looking at powers and grounds to the ECM, like that's our next step.
All right, maybe we're losing a ground right, this Right, we can crank the starter, but it doesn't mean that it's not a ground issue or not a power issue, something like that.
It may be communication, but we don't have any communication codes.
So he goes through, goes through, goes through and ends up checking exactly that powers in the grounds to the ECM and we low tested them and he low tested them on the headlight bulb and we checked them during cranking.
And everything to the PCM Is there the whole time, right, and the inputs to crank the Supply of power and ground to it.
They're all present the whole time.
Nothing ever drops out.
They can all carry a load on those circuits.
So he's not really getting anywhere with it.
And he talks to me and says, hey, this is what I found.
Okay, again, you know, just double check everything, look at this real closely.
Yeah, we don't see anything.
I was like, okay, well, this might be an issue with the ECM.
I Can't be there to check all these circuits, to see all this stuff with myself, but I trust, you know, I trust my employee to make the checks correctly and Be seeing what he's seeing.
And we don't see any other Imports to this ECM that would cause it to release the starter and it's just doing so for some reason.
So we ended up calling an ECM on it, told the shop getting ECM will come back with program this.
So they did that.
They ordered a new ECM for it get installed, we come back, program it.
And it's the same thing.
I didn't change anything at all and I got that call and like, okay, well, it's just gonna have to be something that waits until I get back and I will take a look at it personally and we'll see if we can get through this.
So you know, apologize to the shop and say, hey, we're gonna take care of you, we're gonna take care of you either way, we'll get this solved.
And you know we'll eat the module.
You don't have to worry about that.
All right, it's our bad call and I'm happy to do that.
If we make a bad call and something, I'll pay for the parts.
I'm not gonna have them eat the part of the customer.
Eat the part Because I made a bad call.
Absolutely not.
But you know mistakes happen.
So you Get back into town, get on this thing.
I get down there and experience the exact same thing.
You know everything is exactly like Steve was telling me.
It is all of the tests that he did.
Essentially I did the same thing, just to verify it.
Like I want to see it myself, I can crank that starter over by jumping that relay.
It cranks over, seems no problem, right, I kind of drained their battery down so I hooked up my jump pack and so same thing cranks over.
Okay, I verify that.
The ECM is definitely dropping out the relay control.
For sure, there are no codes, there are no data pins in the ECM that can help me and there is about a gazillion data pins in these things.
For go a little overboard.
But you know, I'm looking at the actual start relay command and this was interesting in this.
I wasn't clear on number one to tell Steve to look at or To even know that it was necessarily there.
I don't know all the data pins off the top of my head.
There's a starter relay data pit in the P in the ECM and that actually Switches and this is one thing that you can see in the ECM that, hey, it's commanding or it is intentionally releasing the starter relay because it goes from on when it first hits the starter to off.
Okay, well, and that's not a huge help because we know that's happening, we know it's releasing it, but it's there and scan data.
This isn't something necessarily like weird circuit issue with those command wires.
This is the ECM's logic telling it that, hey, I'm releasing this starter.
Okay, well, I guess that's something.
And of course, again I want to look at the voltage data pins, the key position data pins, the park neutral data Pids, and look to see is there any kind of dropout on these while this is happening?
Is it losing something and an important input to it that would prevent it from cranking?
And I don't see any.
And again, I checked the anti theft stuff, even though I didn't think that was related.
Again, all of that looks fine.
I don't see anything.
Scan to a wise.
It's causing this dropout.
And Hindsight here I I really would have liked to have taken a closer look at At one of the data inputs.
Maybe I would have seen something.
But I'm I'm pretty darn certain that I looked at it and I grafted and I didn't see a dropout.
Now I'll get back to what that is.
You'll hear what the actual solution was to this.
But I went back and forth, checking a few things and checking powers and grounds to the the ECM, and Didn't come up with any solution and eventually what I got to was I was really trying to make myself a list of okay, because the ECM is deciding to release the starter, what are the things that could Cause it to do this, like right, under normal circumstances, what are the things that are going to change
, or the inputs that are important to the ECM to allow it to crank or not.
And, and obviously, key position is important one, and this is a bladed key if I didn't mention that, but the key position is important and that looked okay in the scantable.
But also the park neutral position is really important on these vehicles and any vehicle, right, that's not anything new, but it is an input to that module.
And so, again, I had already really kind of looked at the crank inputs as closely as I could have and looked at them on the circuit and didn't see anything but the park neutral input.
I really hadn't looked at too much, and reason being is it showed fine on the scan tool and the ECM, as far as what I could see.
But there's an independent circuit that goes between the TCM and ECM to indicate the park neutral position, right, are we in park or are we in neutral?
And the TCM, which?
This is one of those automatically shifted manual transmissions at the DPS 6.
These things are just garbage and they have the Transmission control modules bolted to the case of these transmissions and A lot of issues with these transmissions, a ton of issues.
This isn't, you know, one that I've seen is an issue here.
But I start looking at this circuit and again, there's an independent circuit here of Park neutral on this thing and I hadn't really looked closely at this circuit, looked at the data pit I didn't look at the circuit, and I don't think Steve did either, or the shop and Once I've got the scope out here and I'm looking at stuff, I did see a dropout on this wire.
Okay, and so this is just a simple Voltage on this wire, like a real simple on or off, depending if you're in park neutral or not and that's the indication to the ECM whether the transmission is in the correct gear range to crank.
Okay, well, hey, we're finally on to something here.
Now again, why I didn't see this in my scan tool, I don't know, was my scandal.
I was using and yes, it was an aftermarket one that I was using here.
I did not have IDS on this thing when I was graphing.
Hindsight, maybe I should have.
I never even did try it, but I have something here to go with, so I don't really care at this point.
I just need to follow this and figure out Okay, why is the park neutral dropping out?
And it makes sense.
Why the starters releasing?
Because it doesn't see it that it's in the correct gear to park, to crank anymore, all right.
So Now I really want to focus on my TCM Transmission Neutral Module.
There wasn't any codes in this thing either, and I go into the data pits for this control module at this point because I want to see do I see anything reflected here that's indicated that, hey, we're leaving park or neutral?
Now, one thing that I noticed here was that the the prindle on the dash that indicated the gear position would go blank when you were cranking Right.
So if you held that key forward, it would just go to no gears indicated, and I thought in the moment I was like well, this must be part of my issue.
It's like losing its capability to understand if it's in park or neutral.
I did find out, and I want to make this clear.
That's normal.
That happens when you crank it, even if everything is good.
So don't go off of the prindle going blank as a problem in this one.
It's not, but I did look at the data pits and this was a little bit confusing.
This is where it this one was just odd.
This is a strange one.
There's a range sensor on this transmission that sits on the top and it's an independent sensor and it feeds the TCM through a few circuits and it actually outputs like a duty cycle to the transmission control module to indicate the position of the transmission park or neutral drive flow, the status that this output and there's a number of data pits in the TCM for this never changes.
You can crank it.
It releases a starter that never goes away from park.
Because that's what I was thinking.
I was like maybe this is like a range sensor issue or something like that Never changes.
And I should note I never lose communication with the TCM.
Nothing ever drops out.
Scan tools side, again, don't have any communication codes, they've nothing like that.
Okay, and I'm looking closer.
I'm looking at all the data pits I can here because I'd like to get what I can from scan tool info before I go Digging in circuit wise.
I want to know you know what?
Where am I losing this?
Is it in turtle the module.
Is it dropping out for some reason?
Or is there something else going on?
And that's what I was trying to determine.
Was it losing something from the actual range sensor?
Is this in the TCM?
Which direction are we going?
And again, I don't see anything there.
Now, scouring the data business took me a little while.
I did find two data pits that would actually drop out and correlate with my problem.
Okay, so the first one here the abbreviation to this is TR crank in the TCM and this says transmission range input allowing start, and that data pit, when this thing would release the starter, would go to no, otherwise it would be yes.
Right, if you turn the key on it's in park, it says yes, meaning that the TCM is allowing cranking.
If you put it in reverse, it says no.
But if you put it in Parker neutral, it says yes.
And you go to crank it and it still says yes, and then you'd see it drop out and say no on the scan tool, and it correlated right along with my problem.
So again, I'm definitely on to something.
The dropout I was seeing on this circuit between the TCM and the ECM seems to be accurate.
Oh, and maybe I should note Ford calls this thing a PCM.
I'm calling it the ECM, right, I call it PCM.
A PCM it's a powertrain control module into both the engine and trans, and then if it's separate, I say engine and transmission just to be clear.
But if you look at the diagram, ford calls it a PCM still, whatever.
Anyways, the TCM here is my focus and I finally see something happening here.
All right, so why is this?
Because I got the graph right next to each other and the info from the range sensor does not change.
So is this a module issue?
Is there something up with this module?
And once I saw this happening and the way that this thing was acting, right, it would never drop out until you hit the key.
The starter was definitely the key to this actually happening and it was just like, okay, well, this could be a module, but are we back to like a voltage drop issue here, something with the starter?
And I had really kind of eliminated that from my mind because, like I said, initially, we could jump the starter and a single crank all day, but is there something with the starter engaging that's affecting voltage in the system somewhere somehow?
And now I'm kind of back to thinking that, where I totally eliminated that from my mind because you could jump the starter and it would crank all day long.
And again I, you know, I checked my powers and grounds to my ECM, where we were focused in on that, and never found any issues, or with the grounds there either.
But now I'm back in that mindset and again I'm sitting on the driver seat looking at the scan tool.
So I haven't even gone to the TCM yet, but I'm looking at other data pits to see is there anything that can correlate with this, that might clue me in as to what's going on.
And one of the ones I pulled up was the actual module voltage data pit Right.
So this is the voltage that the TCM reads and I tried this thing a number of times.
It seemed okay at first, but every once in a while it would drop out.
Along with that TR crank data pit dropping out.
And they were right along with each other and it would.
The module voltage that it was getting was dropping out.
And then it would come back after the starter released.
And so I'm like I gotta be some sort of voltage drop issue here and I'm not losing communication with the module.
There's no codes in the module for loss of voltage or undervoltage or anything like that.
But I see it drop out very briefly on the graph on my data pits and it again correlates with it releasing.
It's okay for the engine to crank and it's really fast, right.
It's like you're just a tiny little drop on the scan tool and I'm guessing maybe that's why I didn't see it in the ECM, I don't know.
Anyways, okay, let's check powers and grounds to this module, which isn't necessarily the easiest thing.
Number one, because of the location.
Okay, we can lift it up in the air, but the connectors are kind of a pain to get to, the actual like wires as they go in to the module.
Now I can low test the powers and grounds and I don't think that would have gotten me anywhere with this.
And the reason I didn't do that here, right, normally if I'm suspecting a module, I'm gonna take headlight bulb 9000 series, load those powers and grounds.
The reason I didn't do that here is because, again, I'm thinking it's something to do with the starter.
This never changes its status until the starter actually engages Something with the starter.
And I'm thinking voltage drop, there's something going on here.
So what I did was I found the TCM ground, I looked at the diagram, there's like four wires that provide ground to the TCM, but they all go to the same place and this is a ground on the case of the transmission, which is up towards the top of the transmission, facing the front of the vehicle right.
So all four wires go into one and I'm like, hey, before I start pulling these connectors apart or anything like that, because I'm suspicious of the starter right, which is going to use the case of the transmission and the engine as a ground, how about I do some checks here and look for, do we have some voltage drop going on here?
And so this is an easy check to make.
And here's how you do this you take your scope and you can do it with a meter too, if you wanted to, but the scope is nice because you can pause it and zoom in, zoom out and take one lead right, one channel, one lead.
You could use the use scope if you wanted to.
I had my peak go out at this point, I'm getting serious and you take the colored lead and you put it down on the ground that you want to measure and you take the black part of that same lead and you put it up on battery negative.
Okay, now, when I normally crank this thing, maybe I could see a little bit of voltage drop, a few tens of a volt.
Maybe while you're cranking, right, you're gonna see some voltage drop.
That's a lot of voltage, a lot of amperage moving through that circuit and you'll see some voltage drop.
But I don't wanna see too much and what's too much.
If I see a couple of volts at least, I'm going to be concerned about the voltage drop happening here between the negative cable and the case of the transmission.
Right, those are both ground and they should both stay ground.
You shouldn't measure a voltage difference between them, or at least not much, even while you're cranking.
Now here's what I saw when I cranked this thing.
This thing would spike to about nine or 10 volts of difference between this, and this wasn't like a quick little blip on the scope, right.
Sometimes you'll see like a little jump in voltage and you're like, oh, what's that?
And you zoom in, you zoom in, you zoom in and you can't see a separation.
It's just a line as far as you go in on the time base.
But this was like a measurable amount of time.
It actually created a little tiny square wave, if you will, of the voltage drop between these two points.
I'm like, well, this is my problem, right, I'm getting 10 volts of voltage drop between my negative cable in the case of the transmission.
Okay, and again, this, where I'm measuring, is where the ground for the TCM is bolted to the case of the transmission, and so I made sure that it wasn't at that point.
The issue was but I wasn't thinking that was the case, because it was like it's when the starter hits, that's when this is happening.
Okay, so why this is now?
Or?
It should be easy.
I'm just gonna look to see.
Okay, how does the negative battery connect to the transmission case?
And it's a little goofy in the way that it does it.
On this one, it actually goes from negative battery terminal to the body of the vehicle and from the body of the vehicle to the transmission case back by the CV axles or where they go into the transmission case, all right, and there's just one bolt that bolted onto the back of the transmission here.
Okay, well, that's, you know, I can use my scope and start going down the path, right?
Is it a voltage drop from the battery to the body?
And I found out it wasn't, but it is from the body to the case.
Okay, so I get down to the bolt, the big negative cable onto the bottom of the transmission, and I could visibly see I'm gonna.
I'll put a picture on the Facebook group.
You could visibly see where it looked like this thing was acting as an arc welder between the bolt itself and the cable right.
And this was before I even took the bolt out or did anything with this cable.
I'm like, well, this is where my problem is.
There's a ton of voltage drop happening here.
And before I even took it out or did anything with it, I took my jump cable like I actually have a set of jumper cables in the van for jumping dead batteries and I clipped from the case of the transmission up to the negative battery cable and I cranked it and it worked, it started, it cranked all day long, there was no issues, and normally a problem like this it shouldn't be, it shouldn't be as much of a problem as it was right.
If we have a voltage drop like that, right, wouldn't it have stopped the starter from operating?
Well, it obviously didn't, because, like I said and again I'll put up pictures this thing, this cable end, was just toast.
It was all black and the bolt actually.
Interesting enough, when I took the bolt out, the threads like pulled out and I was wondering.
I was like, well, was it because this was stripped?
But I actually think that the voltage drop occurred between the face of the or the eyelid of the cable in the case of the transmission, and the current for the starter was going through the bolt, into the bolt hole and the threads and it just torched this thing.
So you gotta see it, it's pretty wild.
But going back to like, shouldn't this have been a problem that would have been easily identifiable, right?
Why didn't I look at this first?
Why didn't we look at this first?
This is kind of a normal thing.
We see battery cable issues all the time.
We, both me and Steve, completely went away from this because when we jumped the starter relay the thing cranked Like no problem.
Now, after the fact hearing it, it did crank a little bit faster.
When we fixed this bolt we had to clean the connection.
We actually moved it to another bolt because the threads are stripped out of the one that I took out, but anyways, it did okay.
So it cranked a little bit faster, but it wasn't that far off, it didn't sound terrible and it started right.
If you put the key in the on position and you jump the starter relay, it would start.
So it's not like it was cranking too slow to do anything.
But when we would do this we'd have a massive voltage drop on the case of the transmission and that was enough to affect the TCM, but not to drop it off communication, not to kill it, not to set codes, but something with that module.
It goofed up something in that module, enough to release the park neutral position.
I don't know what exactly.
I can't explain that, but that is what was happening.
Is that voltage drop on the ground for the TCM was causing it to stop saying, hey, I'm in park and neutral.
And then the ECM released the starter relay and it was the voltage drop, that big hit of the starter, right, if you look at the amperage spike when you first kick a starter in, it's huge right and that's when your voltage drop is going to be the most Okay.
And my, my, my guess, my assumption is here is that voltage drop was really.
Was that?
Obviously it was really, it was there, but it wasn't enough to completely stop the starter, meaning that when I jumped it manually it could still engage.
And then once it engages and starts moving, that amperage is going to drop down and we were okay with the amount of current moving through this thing.
Right, if you think about a resistance or a restriction to electrical flow, it's more of a problem as you have more current, it's less of a problem as you have less current, right.
And so as that starter mover motor starts moving, we're able to move electrical current through there without an issue, right.
So it gets over that initial hump.
Maybe it's not easy and honestly it didn't sound bad.
But once it gets past that, okay, we're going to keep cranking.
But that initial voltage drop was enough to affect the TCM that's using that case for a ground as well.
Right, that module was more sensitive than the starter itself, surprisingly enough.
If you would have told me that's what was going on with this one and that's how the problem presented itself, I don't know if I would have believed you, but I saw it.
That's what it was for sure, because we fixed up that ground and it was fine and cranked and started and there was no issues.
So that one was pretty crazy.
I mean, looking back on it, maybe there's some things that I should have saw.
I'm really wondering.
Maybe if I had pulled out IDS I would have seen the park neutral dropout in the ECM.
I mean, if I ever have an issue like this again because my first thought was a voltage drop and that's what's causing the starter to release I'm going to do a quick check on the block for voltage drop.
I mean, I do this all the time, the voltage drop checks to the block because we see negative cable issues and battery cable issues all the time.
But it's funny how you can do a test and you can just, oh yep, not on, that, stuff's bad.
And that's what we thought when we jumped that starter Not on, that stuff's bad.
We're just skip over it, we're looking elsewhere, we're going down a different path.
So that's why I'm sharing this one, though it's the sort of thing that we run into as technicians.
You know you can define exactly how you might walk through a problem on paper and it looks great, it sounds great, it's technically accurate.
But then you get out there in a real world and, man, these cars will throw some curveballs at you and especially when it comes to control modules, you don't know exactly how they're going to react when there's a problem and there's so many different problems that we can introduce to them, right?
I've seen hundreds of these little focuses and fiestas and I've never seen it do this exact thing.
And maybe I never will again.
Who knows, maybe I will.
I hope I will because then I'll know exactly what to do.
Funny enough, actually, I went to a Land Rover later that day and it didn't crank and it was like the first thing I looked at.
I'm like, oh yeah, I'm going to check the ground.
And this one was funny because I took my test light on the negative battery terminal right the clip ends on the negative battery terminal.
I touched my test light to the block and it lights up and I'm like, okay, all right, and they just left the cable off of the transmission.
So that one wasn't as fun.
But you know, it's just those weird unique problems.
You don't know if you're going to see that exact scenario again, but I learned a lot about the system and it's now burned in my memory in case I get into something like that again and hopefully it helps you out.
Maybe it helps you think about it, maybe it's something that you can look for or at least consider, you know, when you're having this type of issue with a vehicle.
Maybe you just think I'm dumb ass.
You're like Sean, why don't you just check that in the first place?
But that's the way it goes.
So we ate the ECM, but that's.
That's just the cost of doing business and we'll just continue to strive to do better in the future.
That's all we can do.
So I want to thank everybody for listening, really appreciate it.
Hope everybody's out there making some money doing great in the automotive world.
But with that all the way, let's get out there StarFix in the world, one car at a time.
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