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When I put the key end and try to start absolutely nothing happens all lights on the - work but when I turned the key it doesn't do anything I bought a diagnostic programming Bluetooth, the thinkdiag, Cost $109 after connecting I learn there is no communication between the obd 2 port and the PCM also I should Note that the diagnostic Bluetooth tool works fine for my 2016 Dodge journey and 2007 mitsubishi eclipse.. Any help would be greatly Appreciated, I am great with any engine mechanical issues but I am at a loss when it comes to the electrical system.
 

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What year? Electrical systems changed significantly from generation to generation and even year to year.

Do you have power to the PCM relay? If no power to relay, engine wont crank or start and CEL will be off with key in RUN. Is there power to the OBDII port? Scan tool will not work if no 12 V to OBDII port. If I remember correctly, OBDII port is powered from the same circuit as one of the cig lighters.
 
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Are you using a 'chip key' or a plain metal key? What is the history of the car? Did it work at one time? if so when? Model year, as already asked. Have you checked, or better, swappped out the battery. Sometimes a battery looks good but is flat dead. Does the car have a remote start, by chance? ALSO---when the starter gets gummed up with oil, you "TURN KEY" nothing (not even a click--is common. Happened to me last year. Tap the starter with a hammer/pole.
Don't read too much into the OBD at the moment...go back to basics.
 

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Discussion Starter #4
What year? Electrical systems changed significantly from generation to generation and even year to year.

Do you have power to the PCM relay? If no power to relay, engine wont crank or start and CEL will be off with key in RUN. Is there power to the OBDII port? Scan tool will not work if no 12 V to OBDII port. If I remember correctly, OBDII port is powered from the same circuit as one of the cig lighters.
Are you using a 'chip key' or a plain metal key? What is the history of the car? Did it work at one time? if so when? Model year, as already asked. Have you checked, or better, swappped out the battery. Sometimes a battery looks good but is flat dead. Does the car have a remote start, by chance? ALSO---when the starter gets gummed up with oil, you "TURN KEY" nothing (not even a click--is common. Happened to me last year. Tap the starter with a hammer/pole.
Don't read too much into the OBD at the moment...go back to basics.
Wow, I can't believe I left out such important details... It is a 2004 Ford Taurus LX 3.0L vulcan
Yes there is power to the obd2 port(at least my scan tool [ThinkDiag] lights up when I plug it in) I don't know if there is power to the pcm relay.

Yes it does use a transponder key.
The battery is relatively new and test well with my battery maintainer.

The history of the car, (during all this the car cranked fine) is that I had a vacuum leak, it took me a while to locate but I finally found 2 leaks, 1 was the EGR line tube had a Crack so I replaced it & 2 was a split in the emissions/purge return hose (leads from vacuum connector behind throttle body on upper intake manifold to down behind engine to connector next to firewall, passenger side.

After I made these repairs, car ran for two days. Then all of a sudden, no crank. When I turn the key to start, I hear one sudden click, then nothing.

Also, worth noting: I started by check fuses & the 30amp fuse for PCM was blown (Power Dist, under hood), replaced but didn't fix the problem
 

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I would look at the 30 amp fuse again, it blew once and it may have blown again.
 

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I'm not a Vulcan expert. If that was one of my SHO's, I would check the solenoid trigger wire on the starter and also the tried and true - hit the starter with a hammer while someone cranks the car.
 

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When I put the key end and try to start absolutely nothing happens all lights on the - work but when I turned the key it doesn't do anything I bought a diagnostic programming Bluetooth, the thinkdiag, Cost $109 after connecting I learn there is no communication between the obd 2 port and the PCM also I should Note that the diagnostic Bluetooth tool works fine for my 2016 Dodge journey and 2007 mitsubishi eclipse.. Any help would be greatly Appreciated, I am great with any engine mechanical issues but I am at a loss when it comes to the electrical system.
My Son's '01 Taurus had a similar issue when he couldn't start it. Told him make sure transmission shift is fully in Park, and it solved it. Hope U 2 :)
 

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Agree with BOB-O, also try to start with parking brake on and key in, put transmission in neutral and try to start. Could be worn out starter.
 

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Discussion Starter #9
!!PROBLEM SOLVED!!

Thank You
to everyone for taking the time to give advice.
HERE is a summary of the issue & the cause.

Short Answer: Bad Ground, [Wire damaged; Smashed] exposing wires.

You must be thinking; Smashed wire? How would that even happen.
Damn, Trying to delay the part story that makes me look not so bright... lol
Now is where I admit that I alone caused this damage & here's how:

As I mentiond earlier in this post, I had a very difficult to locate vacuum leak, I add to remove the upper air and take manifold To get to the vacuum leak. When I was reattaching the upper air intake manifold it started to get dark and instead of waiting to the next day I kept right on putting it back together & When reattaching the air intake manifold, When bolting it down, there are 4 bolts 1 on the left side of the area intake manifold 25" bolt in the centre and one on the lower right hand side of the air intake manifold. The bolt on the lower right hand side of the manifold Has a ground that Bolts down with the air intake manifold. As shown in the following pic: (circled in RED, it is a black wire with a 1in×1in black box on the end, also does anybody know what this ground is for?)
217406

Due to my impatience or Carelessness or maybe both, I kept right on putting it back together as it was getting dark using the flashlight on my cell phone, obviously something bad is going to happen. Needless to say, without noticing as I attached the ground wire to the bolt the ground wire slid in between the manifold & the air intake. Car drove perfect for 2 days Till the heat from the engine melted the wire and caused a short. Think fully when the short manifest itself the car was parked in my driveway. AsideFrom the fact that I did not have a car for 10 days the time it took me to diagnose the problem and realise it was of my own causing, The only cost was the 30M PCM fuse, about $6.
217407


Again thank you to everybody for the advice 20210113_210411.jpg 20210113_210632.jpg
 

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Yup, that is the noise suppressor. Pinched wire goes from suppressor goes to coil positive terminal so a short to ground will for sure result in a blown high amp fuse.
 

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A short circuit in the +12 Volt supply to the coil pack would never damage the PCM in any way. An internal short in one of the primary windings of the coil pack could possibly damage a coil driver MOSFET in the PCM, but even that is unlikely.
 

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Discussion Starter #15
Yes it did, the short to ground caused the 30amp fuse for the PCM blown and stay blown till the wire was fixed
 
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