2012 3.7L six speed no crank issue

[TARA-fied1]

I'm troubleshooting a "no crank' issue. Below is all I have done so far.
Battery measures 13.26V and is on the tender while testing. Full battery power is measured at positive lead “B” (C197A) on solenoid but no signal at trigger lead “S” (C197B) of solenoid when using key. I jumped across those two and the starter works.


I have tested the starter relay circuit;



#30 is hot as it should be. I found that I didn't have a "control" or energize signal from #85 when using key. Hooking up test light to + on the battery and checking #86 and #87 on the relay connector to solenoid shows a good connection.

So, I checked the clutch safety switch or CPP (clutch pedal position) switch as Ford calls it (there is also a separate switch to disengage cruise control). I have continuity when depressed. It is a "self-adjusting" switch so I reset the adjuster (fully extended) to ensure it was engaging. It self-adjusted when I pressed the clutch pedal and that all works as it should. If I understand the CPP’s function, it should have battery voltage that goes to ground to complete a circuit when depressed. I checked for power. No power to the switch when key is in start position. This seems to be a problem…

I checked the fuses again (I think that was the first thing I did). There is a starter fuse and starter relay in the BEC (bussed electrical center) under the hood. In addition, there is a 20A fuse in the SJB (smart junction box) in passenger kick panel. F27 in the SJB is supposed to feed 12v to ignition switch. I swapped out the various start related fuses and relays in BEC. Still nothing. I have full battery voltage at F27 in SJB. Ignition switch itself seems to be working as it controls all the gauges cycling and the idiot lights coming on and going thru the checks. The door-open dinger with key in ignition also goes off when I pulled F27 to check voltage.

I do not have a PATs security light (picture of a car with a pad lock) on or flashing and it does work. It comes on when I put key to "run" and goes off with all the others after a second or so. I got the doors, trunk latch release, windows, radio, HVAC controls, lights, etc., etc. all working. Battery volts are 13.26. Engine ground checks good. I have checked all the connectors to ensure they are plugged in. So I need to figure out why the CPP is not getting power from the ignition switch with key in start mode which in turn is not energizing the starter relay.
I downloaded FORScan and ordered a OBDlink EX cable. I'll start using that to diagnose further but I have never done that type of diagnostics before...

 

[GlassTop09]

Hi TARA-fied1,

Are you still using the '07's steering column & ignition switch w\ all the '12 wiring, SJB & BEC? Or have you swapped the steering column out to the '12 column as well?

From reading your posting & looking at the wiring diagram, it appears that your issue is most likely located between the ignition switch & the PCM on C175B connector pin #16......the blu-wht wire from ignition switch to PCM......everything else feeds out from the PCM...........

 

[TARA-fied1]

Hello!
I swapped the dash, steering column, cluster, SJB & BEC. For all intents and purposes it is a 2012 Mustang. Body harness, Door harness, locks, EVAP, fuel tank, EPAS, K-Member, brakes, axle, seats, seatbelts, HVAC, EVERYTHING from the wrecked 2012 is in the 07 shell.
Thanks for the input, I'll look at the C175B connector (and pin #16).

 

[GlassTop09]

Hello!
I swapped the dash, steering column, cluster, SJB & BEC. For all intents and purposes it is a 2012 Mustang. Body harness, Door harness, locks, EVAP, fuel tank, EPAS, K-Member, brakes, axle, seats, seatbelts, HVAC, EVERYTHING from the wrecked 2012 is in the 07 shell.
Thanks for the input, I'll look at the C175B connector (and pin #16).

I forgot you pulled all this out of a '12 3.7L............that'd be PCM C1381B connector, same pin #16........you'd probably have already caught that.................
You also might check same PCM C1381B connector pins #37 (PCM grounds this to close starter relay at BEC.....WHT-GRN wire @ SMCS) & pin #7 (PCM supplies 12v+ power to switch side of starter relay at BEC.....YE wire @ SMC) as well as PCM C1381T connector pin #26 (CPP 12v+ power from PCM to same clutch pedal neutral safety switch you've checked earlier for power......BLU-OG wire) ........you sure you don't have PATS interference?

Sorry but had to ask............

BTW, you're doing a damn fine job on this swap...........

 

[TARA-fied1]

thanks for your suggestions and compliments. As for the PATS, I do not know for sure anything! All I can say is the PATS light on gauge cluster doesn't blink or turn on during the attempt to start it. The only time I see it is when I first turn the key to run and all the lights come on and then go out. I did try the key in the door sequence you may be familer with for resetting the security. It didn't change anything. I don't have have a second key unfortunately. But this key worked fine before the swap. Anyway, I will check the things you have identified and I really do appreciate the help! I'll post what I find.

 

[TARA-fied1]

HEY! I think the issue may have presented itself! I went to pull the center connector C1361B (for the 3.7L). As I was just looking things over I noticed for the first time that there may be some damage from the accident. The 12 was rear-ended but appearantly pushed into a ditch or another car and suffered some front-end damage aswell. Anyway, the plastic cover on the outside of the connector was cracked. I hadn't noticed this before. So I removed the cover and the connector is damaged. And where is it damaged?!?! right on pin #16 (and #17 but I don't think it's being used). Now I have to figure out how to repair or replace the connector. I guess unplugging it and yanking it out of the wrecked car disturbed it enough to make the connection fail... thanks again for the help!!!

 

[GlassTop09]

Good deal!
You might check w\ your local Ford dealership & see if they can order the specific connector, then get a set of connector depinning keys & swap the wiring across.

Ford has a listing of all the specific connectors used on each MY\model of vehicle they make.

 

[TARA-fied1]

it turns out that was not the issue. I took it apart. Those wires are actually in the next row over and they aren't damaged after cleaningf them up. SO back to being puzzled...

 

[TARA-fied1]

more random bablings of a crazed lunitic... I unplugged the C1381B connection (which is the bottom one on the PCM). The other one I was looking at was the center one... duh.
Anyway, the "Blue with white tracer" wire is indeed in the pin #16 location! Progress. I put my test light in the pin and worked the key. It comes on whether the clutch is depressed or not!?!? SO what does that mean? I have no idea...

 

[TARA-fied1]

I am going to plug in the PCM connector. I will then try to see if pin #26, the "blue with orange" tracer gets a signal. That should go to the CPP? I think.

 

[TARA-fied1]

well I am out of ideas.

 

[GlassTop09]

more random bablings of a crazed lunitic... I unplugged the C1381B connection (which is the bottom one on the PCM). The other one I was looking at was the center one... duh.
Anyway, the "Blue with white tracer" wire is indeed in the pin #16 location! Progress. I put my test light in the pin and worked the key. It comes on whether the clutch is depressed or not!?!? SO what does that mean? I have no idea...

Hey TARA-fied,

That means that the ignition start voltage signal is getting to the PCM to tell it to go thru it's engine startup sequence, so your no crank issue is not located inside vehicle.

Now check #7 pin on same connector for a 12v+ power coming out of PCM (should be hot at all times), then check 85 side of starter relay for existence of this 12v+ power to tell you if the relay switch side is getting its power to close relay when the 86 side is pulled to grd by PCM after the CPP clutch switch is grd.
Then check pin #26 on C1381T connector for a 12v+ power signal coming out of PCM CPP to go to clutch switch then check again at clutch switch for the 12v+ power after verification it is present at PCM pin #26 (should also be hot at all times). Once all this is verified & you still get no crank, then check pin #37 @ C1381B connector for a grd when key is turned to start position......if no grd is present, then either 1.) PATS is stopping this from occurring or 2.) PCM has an issue on pin #37 (driver can't pull a grd on circuit for some reason).

To ensure this, have someone turn key to start & depress clutch pedal, then you grd the WHT-GRN wire in #37 of C1381B connector.......if engine cranks over, your issue is then isolated to the PCM off pin #37........

 

[TARA-fied1]

Hey TARA-fied,

That means that the ignition start voltage signal is getting to the PCM to tell it to go thru it's engine startup sequence, so your no crank issue is not located inside vehicle.

Now check #7 pin on same connector for a 12v+ power coming out of PCM (should be hot at all times)"it is not hot", then check 85 side of starter relay for existence of this 12v+ power to tell you if the relay switch side is getting its power "also not hot" to close relay when the 86 side is pulled to grd by PCM after the CPP clutch switch is grd.
Then check pin #26 on C1381T connector for a 12v+ power signal coming out of PCM CPP to go to clutch switch then check again at clutch switch for the 12v+ power after verification it is present at PCM pin #26 (should also be hot at all times)"also not hot".

Thanks for the advice! I am so ready to burn this thing to ground. I made comments in red on your quote but basically no power from pin#7 and also no power at 85 on starter relay. I think pin#26 on C1381T is a blue/orange wire? Anyway, no power there either... PCM gone bad?

 

[GlassTop09]

Thanks for the advice! I am so ready to burn this thing to ground. I made comments in red on your quote but basically no power from pin#7 and also no power at 85 on starter relay. I think pin#26 on C1381T is a blue/orange wire? Anyway, no power there either... PCM gone bad?

If you had someone hold the ignition in start position to send start signal to PCM then you took & got the no 12v+ at pins #7 & #26..........there is only 2 reasons why.....1 is PATS is stopping the start sequence or PCM is gone bad.......but there are some other things to do yet before throwing in the towel on the PCM gone bad.

1st thing is to check all fuses that sends 12v+ power & associated relays in BEC to the PCM to ensure that it is actually fully powered up (there are more than 1 12v+ power sources that power up different parts of the PCM for it to fully operate).........

2nd thing is..........do you have the hood off the car? If you do & you haven't physically depressed the PATS hood safety switch (on PS of front fender by the BEC........this is the PATS trigger switch to stop crank if hood is opened w\ or w\o key in switch prior start sequence & usually will lock the car doors if they're closed to tell PCM that car is being stolen. Don't know for sure at the moment if this switch is a NC or NO switch (would inform on how to jumper it thru its connector.......assuming that it is NC) but if you fully depress it (like the hood will if it was on car & closed) this should complete (or open the circuit......depending on electrical circuit setup in PCM) the circuit to PCM to release PATS & start car.

I'm assuming that the '12 also had this PATS hood safety switch installed as well............

I've inadvertently "tested this switch out" on multiple occasions on my '09 GT so I know it's part of PATS (also why I now have a spare bare key in my wallet.......would have locked myself out of my own car while working on it a couple of times w\ the hood up if I hadn't had the DS window already rolled down) ..............

3rd thing is......if depressing this hood switch is a no go, then you'll need to get a tune file set up\flashed in PCM to disable PATS then try to start car...........

If no joy after this, THEN you'll need to consider going down the path to a replacement PCM as the PCM is now ID'd as your issue concerning no crank of your swap.

PS---Welcome to the world of electrical TS'ing........... A tip I'd suggest for you is to go thru the FWM 2011 Description and Operation when you have the time & are not frustrated & read up on all the various systems & how they all operate (yes it's a LOT of reading.....and it's boring.....) as this will greatly speed up your electrical TS skills & assist w\ using wiring diagrams to determine what's what to then follow a set process\sequence of checks\tests so you don't miss anything due to assumption (or building frustration.........been there myself so I know). Oh & get yourself a good DVOM to use along w\ a circuit board safe test light or power probe that can test for power\grounds w\o causing damage to printed circuit boards..........

Take a deep breath, drink a glass of water & refocus (save the alcohol for after you've given up for the day then sleep it off to start fresh the next day).

You'll get it resolved in good order............

 

[Robert Larimer]

If you had someone hold the ignition in start position to send start signal to PCM then you took & got the no 12v+ at pins #7 & #26..........there is only 2 reasons why.....1 is PATS is stopping the start sequence or PCM is gone bad.......but there are some other things to do yet before throwing in the towel on the PCM gone bad.

1st thing is to check all fuses that sends 12v+ power & associated relays in BEC to the PCM to ensure that it is actually fully powered up (there are more than 1 12v+ power sources that power up different parts of the PCM for it to fully operate).........

2nd thing is..........do you have the hood off the car? If you do & you haven't physically depressed the PATS hood safety switch (on PS of front fender by the BEC........this is the PATS trigger switch to stop crank if hood is opened w\ or w\o key in switch prior start sequence & usually will lock the car doors if they're closed to tell PCM that car is being stolen. Don't know for sure at the moment if this switch is a NC or NO switch (would inform on how to jumper it thru its connector.......assuming that it is NC) but if you fully depress it (like the hood will if it was on car & closed) this should complete (or open the circuit......depending on electrical circuit setup in PCM) the circuit to PCM to release PATS & start car.

I'm assuming that the '12 also had this PATS hood safety switch installed as well............

I've inadvertently "tested this switch out" on multiple occasions on my '09 GT so I know it's part of PATS (also why I now have a spare bare key in my wallet.......would have locked myself out of my own car while working on it a couple of times w\ the hood up if I hadn't had the DS window already rolled down) ..............

3rd thing is......if depressing this hood switch is a no go, then you'll need to get a tune file set up\flashed in PCM to disable PATS then try to start car...........

If no joy after this, THEN you'll need to consider going down the path to a replacement PCM as the PCM is now ID'd as your issue concerning no crank of your swap.

PS---Welcome to the world of electrical TS'ing........... A tip I'd suggest for you is to go thru the FWM 2011 Description and Operation when you have the time & are not frustrated & read up on all the various systems & how they all operate (yes it's a LOT of reading.....and it's boring.....) as this will greatly speed up your electrical TS skills & assist w\ using wiring diagrams to determine what's what to then follow a set process\sequence of checks\tests so you don't miss anything due to assumption (or building frustration.........been there myself so I know). Oh & get yourself a good DVOM to use along w\ a circuit board safe test light or power probe that can test for power\grounds w\o causing damage to printed circuit boards..........

Take a deep breath, drink a glass of water & refocus (save the alcohol for after you've given up for the day then sleep it off to start fresh the next day).

You'll get it resolved in good order............

Are you saying that a 2012 Mustang will not start with the hood up? I just tried it with mine and it started right up no problem. It does have a sensor for the hood though. I have no idea what it does. I do not get a hood ajar notice like the trunk does.

 

[TARA-fied1]

1st thing is to check all fuses that sends 12v+ power & associated relays in BEC to the PCM to ensure that it is actually fully powered up (there are more than 1 12v+ power sources that power up different parts of the PCM for it to fully operate).........

I will double check these but I have gone thru them looking for a bad fuse or relay

2nd thing is..........do you have the hood off the car?
I'm assuming that the '12 also had this PATS hood safety switch installed as well............

hood is off the car but there was nothing in the harness from the 12 like that. The 12 would start with the hood off, in fact it didn't have a hood when I bought it and test drove it.

3rd thing is......if depressing this hood switch is a no go, then you'll need to get a tune file set up\flashed in PCM to disable PATS then try to start car...........

If no joy after this, THEN you'll need to consider going down the path to a replacement PCM as the PCM is now ID'd as your issue concerning no crank of your swap.

PS---Welcome to the world of electrical TS'ing........... A tip I'd suggest for you is to go thru the FWM 2011 Description and Operation when you have the time & are not frustrated & read up on all the various systems & how they all operate (yes it's a LOT of reading.....and it's boring.....) as this will greatly speed up your electrical TS skills & assist w\ using wiring diagrams to determine what's what to then follow a set process\sequence of checks\tests so you don't miss anything due to assumption (or building frustration.........been there myself so I know). Oh & get yourself a good DVOM to use along w\ a circuit board safe test light or power probe that can test for power\grounds w\o causing damage to printed circuit boards..........

Take a deep breath, drink a glass of water & refocus (save the alcohol for after you've given up for the day then sleep it off to start fresh the next day).

You'll get it resolved in good order............

Thanks so much for taking the time for the detail replies!!! I have ordered the manual. By the way, what is a DVOM?

 

[Robert Larimer]

I will double check these but I have gone thru them looking for a bad fuse or relay

hood is off the car but there was nothing in the harness from the 12 like that. The 12 would start with the hood off, in fact it didn't have a hood when I bought it and test drove it.

Thanks so much for taking the time for the detail replies!!! I have ordered the manual. By the way, what is a DVOM?

My 2012 has a hood open sensor mounted on the back edge of the hood opening near the driver. It has a flat black wire connected to it that runs down behind the engine. It does start fine with the hood open and I have no idea what that sensor is for.

 

[TARA-fied1]

My 2012 has a hood open sensor mounted on the back edge of the hood opening near the driver. It has a flat black wire connected to it that runs down behind the engine. It does start fine with the hood open and I have no idea what that sensor is for.

This is/was a base model. Not sure if it’s a premium thing or not but mine doesn’t have one at all.


Sent from my iPhone using Tapatalk

 

[Robert Larimer]

This is/was a base model. Not sure if it’s a premium thing or not but mine doesn’t have one at all.


Sent from my iPhone using Tapatalk

I have a premium pony package so that might be true. I did a little searching and the best I can come up with is that the sensor is for the optional anti-theft package that I don't have. Did you ever find out if the stock hood clears the 3.7? I am curious if the bulge in hood of the 2010 redesign was to clear the Cyclone engine. It is taller than the Coyote.

 

[TARA-fied1]

Did you ever find out if the stock hood clears the 3.7? I am curious if the bulge in hood of the 2010 redesign was to clear the Cyclone engine. It is taller than the Coyote.

I have not put the hood on yet. I might just sell all the parts and junk it anyway...