My 427 SOHC Build..... Finally the time has come!

[Cyclone03]

sorry for just jumping in,whats up,car wont start with key? unplug the clutch switch and put a jumper in the car side connector try that. If that doesnt work its not the switch. Does the harness use a neutral safety too? If it's not hooked up the results are the same,no crank. Find that connector and jump it too.
If I read correctly you have some kind of alarm system,find the box,then remove every wire attached to it and restore the car wiring harness to original. I dont care whos system it is they are all crap and unserviceable if something goes wrong inside,just chuck it all.

My Optima cranked and started my FI 433ci FE with just 9v on the gauge at key on,dropped to 6v while cranking.   

[My427stang]

Jumped the starter with a screw driver.  The starter works for sure.

OK, so the battery is good enough.  You could jump to make sure, but the starter pulls a lot more power than the relays.

So IMHO, it really is test light and wife time.  Start with the wire to the starter, have your wife step on the clutch and turn the key, it lights up brightly or doesn't.  It likely won't, so you work back in the wiring diagram, each point having your wife do the same thing.

Sometimes, you may find that a wire is broken or crushed somewhere as you test one area but the next doesn't make sense. As Heo said, it may be sensitive enough to show voltage, but a standard bulb would be dim or not light.

In the end, if it worked before you sent the motor off to Jay, either you damaged a wire, left something unhooked, or something failed (like a relay or the aftermarket alarm)  all of them are viable, but as much as everyone wants to help, 12.2 to 11.4 really doesn't say much, you eventually have to know the circuit, then just follow it back until you find the cause.

BTW, I would lose that alarm if it is easy to bypass.  If you have a chipped keyset it'll keep the crappy thieves away, and the good ones will cut the battery cable and stuff it in a trailer anyway.

[Cyclone03]

Let me tell you a story about Volt meters or a digital multimeter
My Galaxie  before i owned it had no brake lights. They spent a
whole day chasing some mysterious fault in the electrical system
12.something reading in the brakelight socket with a shiny new
super duper multimeter from the electronics company a friend
works at. New bulbs, still no brakelights.I asked if the had tested
the bulbs, Noo they are new,  I tested one on the battery nothing
wrong with the bulbs then i tested the socket with a test bulb,nothing
they showed me 12.something with the multimeter
I pulled the cables from the brakelight switch and cleaned them. Voila
brake lights The multimeter was to sensitive made for measuring microamps
the bad connection let through enough to trigger the multimeter but
not enough to light up the bulbs

I chased a slow battery draining issue for weeks,it was the master cylinder mounted brake light switch on a 64 Gal.

[cobracammer]

Picking up a test light today.

So good battery, good starter, good ignition switch, good at the SJB fuse, good at the pigtal to starter safety switch, tested clutch switch for ohms but a jumper wire will be a better test.  Will post back after I get the test light and test the starter signal wire under the car again.

[Nightmist66]

One more quick test if you suspect the relay. Swap the relay with another of the like and try again. If it works, you found your problem, if not, you probably have a wiring issue. Just because the relay clicks, doesn't mean it is fine. I have seen my fair share of high resistances through the high current side of the relay itself. Good luck!

[cobracammer]

Thanks Jared.  I had forgot to mention that I tried that already. No luck.  The old one clicks, and I swapped it for the relay next to it ( i think is the High speed fan) and it clicked too.  But did not start.  Thank you for the suggestion though. 

I picked up a tester light today from Auto Zone.  I will go out there tomorrow and start with the signal wire to the starter..... And work my way backwards 

[cobracammer]

Ok gentlemen.  Got under there today with the tester light.  First stop was under the car to test the signal wire.  Test light says..... NO SIGNAL.  Just as you all were saying, voltmeter registers ( im guessing something like millivolrs) but in reality nothing.  So from there, i tested the pigtail wiring at the clutch starter safety switch.  Pulled off the actual switch, and with the key in the start position, test light comes on.  Then tested other wire on the pigtail in start position and nothing.  This is correct because its a switch and one side should be power in and the other power out.  So either switch is bad or the relay.  I will try a jumper wire to bypass switch and narrow it down to the culprit.  Thanks again guys

[cobracammer]

Ok.  Made a jumper wire for the pigtail.  Inserted it and turned the key.... Nothing.  Then swapped out the relay again in the bussed electrical center again ( last stop before signal to starter) and nothing.  Definately a problem between power into clutch safety switch and the starter.  Jumper wire did not work and jumper with a different relay did not work.  Thoughts?

[Heo]

Do you have signal in to the relay? do you have signal after the relay?
Test! don't just listen to the relay clicking if you have signal after the relay
its something with the wire from relay to starter bad connections.maybe when
you pulled the engine the wire hooked to something and almost tore a
pigtail of

[cobracammer]

The relay is in a pretty hefty 2 level fuse box/ electric panel.  How whould I go about testing?  The wire that comes out of the relay ( bussed panel) goes to the solenoid on the starter and there is no signal there.  I just got finished testing the clutch switch ( ; times in a row) and the switch is good for sure.  Would like to know how to test power into and out of a relay.  Any thoughts?

[Nightmist66]

If you are testing the relay circuit, and you hear the relay click, you want to look for terminal 30 and 87 of the relay. Terminals 85 and 86 are always the low current coil side and you know that is working if it clicked. It should be marked on the side or usually the bottom of the relay.  Check for power at one of these terminals in the SJB with relay removed of course. If terminal 30 or 87(depending) have power, try running a jumper wire or paper clip between these two to bypass the relay. If it works, you have a bad relay. If not, you either have high resistance in the circuit exiting the relay or an open circuit(broken wire).

If it is possible, it would help a bunch if you could attach a wiring diagram to help others here diagnose with you.

[Heo]

+ what he said. And the testlights often have a sharp needle that you can
push through the insulation on the wire to test. If you jump the relay and
still have no signal att the starter trye to penetrate the wire a couple of
inches away from the starter to see if you have signal there

[cobracammer]

30 has power at all times.  Put testlight in each of the other pin holes one at a time while clutch depressed and key in the start position and no other pin location has power.  30 has constant power though

Wire diagram for starter and ignition on previous page.  Ill look for a diagram of the relay now

[cobracammer]

Also, there is a note on my diagram that the starter relay is supplied ground from the PCM.  If that assists anyone.

[Nightmist66]

I can see why it won't start now if 30 is the only one being powered. It may have been another relay you heard clicking but it couldn't have been this one. At any rate, you should be able to jump 30 and 87 and see if it cranks and the circuit is working. You will have to find out why terminal 85 or 86 doesn't have power supply. That sounds like you're problem. You may want to check fuses first and see if one is blown for the starting circuit. It may be that simple. Something could've gotten shorted by accident at some point. If it is not the fuse, you will have to back track. Hope this helps.