Starter solenoid/ignition wiring??????

Sorry kinda long.....

OK guys I am getting my butt kicked

Brand new starter solenoid (appears fine not welding itself on)
brand new ignition switch
Cleaned up column pin/rod assembly (not sure technical term)
All alternator wires disconnected except large one to the battery side of solenoid
Key action is smooth and returning from crank position to run position very nicely.

No matter what configuration between the S and I terminals I have the starter starts to crank in the RUN position and continues on cranking even with the key pulled out in the lock position UNTIL I disconnect the S terminal wire on the solenoid. Tried switch S and I both do this same thing.

With NO wire on the I terminal starter starts cranking in the RUN position but shuts off when you go back to the LOCK position. Again tried switching the wires both do the same thing.

The solenoid is not welding itself shut, after removing the S terminal there is NO CONTINUITY between the battery terminal and the starter terminal.


What am I missing here guys? Is it something to do with the voltage regulator under the solenoid? I should be removing this anyways with my 130 amp alternator correct? Or not having the alternator completely wired in?

Just trying to take one step at a time and atleast get it to crank like it is suppose to first

 

Your first problem is that you should NOT have +12V dc on the "S" terminal of the solenoid unless your keyswitch is in the "Start" position....not the "Run" position. The Red/Light Blue, should be the only wire on the "S" terminal of the solenoid.

Go back and check the keyswitch first.

 

And more....

There are TWO SEPARATE CONTACTS THAT CLOSE in the solenoid, when cranking the keyswitch/starter in the "Start" position:

1. The MAIN contact closes (the large terminals on the solenoid) which connect the battery's positive voltage to the starter.

2. The smaller "coil boost" contact closes in the solenoid, connecting the battery positve to the "I" terminal, which leads to the coil's primary, and is for applying extra power to the coil during starting.

Make sure your ignition wiring is like this:

 

And...if your new 130 amp alternator has a built-in voltage regulator...then yes...you will be rewiring your system, along with excluding your factory voltage regulator.

 

Ran into a similar problem when I rewired for EFI. The TFI module requires power in start and run during crank and the factory Maverick wiring only provides that power to the ignition circuit via the solenoid on the red/grn wire that cactusgrabber mentioned. I had to install a diode in the start circuit to allow the solenoid to get power when in start but to break the circuit when the key goes back to run. Have you done any mods to the ignition circuit that would produce a backfeed of voltage on the start circuit during run?

Don't overlook the neutral switch. It has a power feed for the back up lamps that could bridge the start circuit to ignition power too.

 

OK so my thinking here is correct thats good to know

On the stud on the solenoid this is the only wire, no other wires on the stud.

Also being the ignition switch is brand new I do not see or think there could be a problem here

 

So bassically, the S terminal should be hot in the START position only activating the starter solenoid, and the I terminal pretty much can just go straight to the positive side of the coil for power during cranking while another wire on the positive side of the coil that is hot during run only.

So basically the solenoid is a simple double pole double throw relay, that is activated from the 12volts to the S terminal and ground through its mounting frame to complete the curcuit on the coil?
^^^^^^
Can someone double check my thinking here?


So while looking at the wiring diagram the only thing I can really think that would be causing me some sort of "back feed" would be in the neutral safety switch setup, the voltage regulator, or wherever that yellow fusible link wire is going (any one have the other section of the diagram to where that leads?).

Thanks for the wiring diagram Roger

 

You say "brand new ignition switch"... Are you referring to the actual switch or the key lock assembly?

There is an adjustment procedure for the switch, did you do this? There is a pinhole that you run a 1/8" (or 3/16"?) drill bit into, when the bit goes through the switch and a matching hole in the column, the adjustment is correct.

 

Yes I believe it does.

My alternator is out of a 95 mustang 3.8

it has a (= where I think they go, not wired in yet)
B+ wire= should be going to the battery side of the starter solenoid with an inline 175 megafuse

A Wire= should go to the same battery side of the starter solenoid

S wire= loops back to a plug back into the alternator

I wire= not sure where this one is suppose to go with the old regulator being removed????? I believe the old I terminal wire when the old regulator is removed.

And the remove old regulator, not sure what to do with trhe old wires on the plug.

 

Referring to the actual electrical switch activated by that rod assembly running down the column.

Whoops no on the adjustment procedure, just kinda did it by feel while cycling the key. Never knew there was such a procedure

Do you happen to have a write up explaining the procedure in more detail, or care to give me a little more of a write up?

 

Okay Adam...we're still at a point of needing to trace the start wire back, while disconnected from the "S" on the solenoid.

InjectedMav is right...the start control wire might be coming in contact with voltage from the neutral safety/reverse lights switch. (steering column on column shift cars, and on tranny on floor shift cars).

The other possible spot the "start" wire is in the vicinity of hot wires, is at the engine wiring harness main plug, on the engine firewall.

I would open the start wire at the engine firewall plug area, and check to see if you still have voltage on your start wire, while the key is in the "run" position. That will at least rule out half the run...and tell you which side of the firewall the problems is coming from.

Make sure everything that should be grounded...is grounded...including the solenoid.

If you want...I can come over and give you a hand on a weeknight this week...or this weekend. Let us know what you find. Good Luck!

 

What starter are you running with the T5? I am running the 93 mustang mini starter and it is wired a little different. It has its own solenoid on the starter.

 

Old school starter not the mini starter. So say from an 87 mustang

 

Thanks Roger, If I need a hand I will let you kn ow, I will give it a couple more trys before asking you to drive all the way across town but I appreciate the offer


I am going to start by finishing up the alternator install and get that voltage regulator out of the mix. Can somone double check me on my wiring I posted above concerning the alternator?

Then go through that column electrical and double check that. I have had it apart a few times lately I very well have something touching thats not suppose to be causing me my problem. As well as double checking the "location" of the ignition switch using the drill bit to set it.

Then backprobe at the firewall on the S wire to rule out half the area like you suggested.

Thanks

 

I had this same issue when installing a new solenoid. Turns out wiring was right, the solenoid itself was sticking internally. I would try giving it a good tap or two with a screwdriver and see if it frees up.