Ok I have a mustang I changed the trans in. It ran before changing trans and now it doesn’t want to start with the key can jump it with a paper clip from fuse/relay box under hood but as soon as I turn the key off and try to start it with the key it won’t start back up. It has a new starter new ignition switch and neutral safety switch that has been lined back up. I’m lost and can’t quiet figure it out. I’m thinking of running a momentary on off switch but I’m not sure if it would hurt the car considering it has the pats system. Please get back to me on this thanks.
Your 2000 Mustang uses PATS Type "C". It DOES NOT have a starter interrupt. If you're turning your key to START and the starter isn't turning it isn't the PATS "C" causing it.
Another thing about PATS Type "C". If the engine runs for more than 3 seconds and then dies it's NOT the PATS causing it. PATS Type "C" will cut power to the fuel system within 3 seconds of turning the key if the key isn't verified by PATS.
So when a different version of PATS disables the starter (yours doesn't) it does so by removing the ground from the "control side" of the starter relay's coil.
You guys started the Mustang by jumping starter relay socket terminals 30 & 87.
The other 2 terminals are 85 & 86,
I'm pretty sure the Ground is on starter relay socket terminal 85. Since yours doesn't have "Starter Interrupt" that socket should have ground all the time. Use a test light to check that.
When the Key is in START, starter relay socket terminal 86 should have battery voltage.
If it doesn't then work your way back through the circuit to the ignition switch.
1st check for power going into that Neutral Safety switch you replaced and check for power coming out of it in Park/Neutral.
If you don't have power going into there, then check the wiring/connector for damage/corrosion.
Then check the ignition switch's STA terminal with the key in START to be sure it's getting power. If not, work your way back to the fuses protecting the power input wires to the ignition switch. Make sure all the ignition switches b+ terminals are getting power.
This may just be a faulty ignition switch or it's wiring/connector or a Ground like @justin-shepherd mentioned. (I know you said it's new but I was walking a guy through a similar issue on a Ranger about a month ago. He replaced the ignition switch. When I had him test the power IN and OUT of the switch it wasn't right. He returned the switch, exchanged it for another new switch, and that one worked)
It should be pretty easy to nail down where this problem is. Test one thing at a time. If there's a problem, trace down the reason (bad ground, Fuse, wiring, component) BEFORE moving on to the next side of the Starter relay control circuit
Did you try to replace the relay? Usually relays are somewhat interchangeable in the fuse box and you can do a quick swap with one that you know works. If it matches. Providing I'm understanding what you mean when you say you're "jumping" the fuse box/ relay.
In my own experience, I was testing the horn relay in my 1999 Ranger a couple years ago by swapping the horn relay with the headlight relay since they were the same. The horn honked again but the headlights wouldn't work when I did the swap. When swapping them back, the working relay shot out of my hand when I pulled it out and it went into the abyss of the engine bay without falling to the pavement. That was a $30 mistake, but new relays got them all working again.
Yes the relay made no differen I even checked my grounds still nothing it’s like the car has been immobilized or something which I believe the pats system can do
Also it’s a base model 2000 mustang
What are you jumping that is letting it start? An immobilizer won't let you start it by jumping jt.
The relay spot for the starter relay
This might be of use. Somebody has the same issue.
Sounds like you have an electrical problem, recheck the ignition switch and such https://www.fordforumsonline.com/threads/2000-ford-mustang-no-signal-to-starter-relay.46886/