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RetiredBMC
03-12-2017, 06:51 PM
Greetings Thunderbirders....I'm restoring a 62 T Bird hardtop and I ran into an issue that is kicking my butt!! So far I have replaced the ignition switch, ignition coil, voltage regulator and the solenoid and generator are only about a month or two old. The car was running perfect until I changed out the old battery cables because they were all beat up. Went to start the car......perfect....went to turn the key to off and pulled the key out of the ignition and the car continues to run. I was able to get the car turned off by blocking off the air intake. I'm at a lost here.....anyone ever have an issue like this before?

Thanks in advance.

jopizz
03-12-2017, 07:35 PM
For your car to turn off your ignition switch needs to shut off power to the coil. The battery cables should have nothing to do with it. Check the + terminal at the coil with the key off. You should have no voltage. Turn the key to on and it should have between 6 and 9 volts. If you have power with the key off then your switch is bad. Did you change out the ignition switch before or after the problem started.

John

RetiredBMC
03-12-2017, 09:26 PM
I changed out the ignition switch after I discovered the problem....that was the first thing I tried.....so far, I'm striking out...lol

jopizz
03-12-2017, 10:08 PM
Rather than replace parts you need to follow the basics of troubleshooting ignition systems. All replacing parts does is add unknowns to the problem. The ignition system in your car is very basic. It involves power from the battery to the ignition switch to the coil. It's either off or on. You need to use either a test light or voltmeter to diagnose the problem. The wiring diagrams are available in the Technical Resource Library. They are very easy to follow. Does this happen every time you start the car or is it sporadic. One suggestion I can make is when it happens remove the small brown wire that is on the front of the solenoid. If the engine shuts off then you have power going through the solenoid when it shouldn't be. If the car continues to run then you will have to look further down the line.

John

simplyconnected
03-12-2017, 10:55 PM
I'm totally with John on this. You end up with a basket full of good parts you cannot return when throwing parts at a problem.

John, is it possible his firewall plug is shorted? That is a notorious place where corrosion opens and shorts pins. Maybe you can assist from here. - Dave

jopizz
03-12-2017, 11:20 PM
John, is it possible his firewall plug is shorted? That is a notorious place where corrosion opens and shorts pins. Maybe you can assist from here. - Dave

That's certainly a possibility. It strikes me as odd that he says it started when he replaced the battery cables. Maybe he caused some voltage spike that fried the connector. That should be easy enough to pull apart and check.

John

RetiredBMC
03-13-2017, 07:38 AM
That's certainly a possibility. It strikes me as odd that he says it started when he replaced the battery cables. Maybe he caused some voltage spike that fried the connector. That should be easy enough to pull apart and check.

John

You'll have to forgive my ignorance......but where would that connector be located at?

RetiredBMC
03-13-2017, 07:42 AM
I'm totally with John on this. You end up with a basket full of good parts you cannot return when throwing parts at a problem.


Very true....unfortunately my pride won't let me ask for help until I've tried everything I think I know....lol.

Yadkin
03-13-2017, 09:06 AM
Don't sweat it- we've all been there.

jopizz
03-13-2017, 11:43 AM
You'll have to forgive my ignorance......but where would that connector be located at?

Look on the driver side firewall below the master cylinder.

John

simplyconnected
03-13-2017, 02:53 PM
Very true....unfortunately my pride won't let me ask for help until I've tried everything I think I know....lol.Get those thoughts behind you, quickly. This international site is founded on friends who are here for guys just like you, so we can HELP with your problems.

Please allow us to work on your issues together. All of us started out knowing nothing. I've had great help from the engineers who designed your car at Ford because they were eager to share their career passion. We want to see your car on the road.

BTW, your problems have been shared in the past so, you're not alone. Feel free to ask because all questions are important, not only to you but to others who might have the same problems. - Dave

RetiredBMC
03-13-2017, 05:30 PM
Haven't found it yet........however, I did find 3 wires....one white that runs with 2 red wires all taped up that run along the top of the block behind the valve covers (white connects to top of oil filter unit) red that goes the top of the engine block (sending unit?) and the red that goes to the + terminal on the ignition coil....all 3 of these wires had "breaks" in the insulation and some points of the wire were melted from the engine heat and the copper wire inside was exposed.....these wires lead straight back to the firewall, drivers side. There were also 2 green wires, those go to the master cylinder...those I know are for the break lights...replaced that sending unit already :-). I'm cutting those out and splicing new wires in.....hopefully, that was the source of my troubles???? wish me luck.....or....tell me if I'm screwing up...lol. I seriously owe you guys a cold one for all your help....I really do appreciate you patience and wisdome here

jopizz
03-13-2017, 06:37 PM
The white/red wire goes to your oil sender, the red/white goes to your temp sender. Those wires are normally not hot when the key is turned off so I don't think that is the cause of your issue; however the brake light switch wires could cause a problem if they were shorted to your coil wire. I agree that you should repair any bare wires and see if that fixes your problem.

John

simplyconnected
03-13-2017, 06:46 PM
Follow the wires on your starter solenoid. One is yellow, another is red/blue. They should be in the same firewall plug as your temp and oil sensor wires.

The plug needs to be disconnected so you can see the pins inside. This is important because water can corrode the insides. - Dave

jopizz
03-13-2017, 06:49 PM
Here's a diagram showing the two main connector plugs. They are below and to the right of the master cylinder/booster.

John

simplyconnected
03-13-2017, 07:44 PM
Ok, look at what's happening in this plug. One wire for the brake switch is hot at all times and two wires go to the starter solenoid. One wire bypasses the ignition resistor to the coil.

I would start by looking at this plug:

RetiredBMC
03-13-2017, 10:55 PM
Sorry, I got busy....all great info...thanks. So, here's what happened tonight. I replaced all those broken frayed wires, hooked up the battery and took the volt meter to the wires. With the ignition OFF, no key, I was getting 13 volts at the red wire that attaches to the ignition coil +. So, go inside to the ignition switch (my entire dash is removed) and I see a separate red wire leading up and away from the ignition switch that has a quick disconnect/connect plug that goes into another bundle of wires. I disconnect if from the ignition switch and put the volt meter to it and I get 13 volts as well. Looking in my shop manual, I believe it is the "Spark Coil Primary Resistor" I'll try to attach the phone here. So........if I am getting 13 volts on the red wire (primary resistor) going into the ignition switch, and it's turned OFF and I'm getting 13 Volts at the red wire that is suppose to connect to the ignition coil....does that mean bad ignition switch? Hopefully I explained it right.

RetiredBMC
03-13-2017, 11:01 PM
I was going to post a picture from the shop manual...but can't seem to get it to work...sorry.

RetiredBMC
03-13-2017, 11:02 PM
Here's a diagram showing the two main connector plugs. They are below and to the right of the master cylinder/booster.

John


Awesome!!! Thanks, I was able to locate the connector :-)

jopizz
03-14-2017, 12:15 AM
So........if I am getting 13 volts on the red wire (primary resistor) going into the ignition switch, and it's turned OFF and I'm getting 13 Volts at the red wire that is suppose to connect to the ignition coil....does that mean bad ignition switch? Hopefully I explained it right.

With the key off the only wire at the ignition switch that should have voltage is the yellow wire. None of the other wires should have voltage unless the key is in the On, Acc or Start position. If you have voltage on the resistance wire bullet connector coming from the ignition switch with the wire disconnected and the key off then it's most likely the ignition switch. To make sure remove the connector from the ignition switch and put your voltmeter on Ohms with an audible beep. Make sure the key is off. Connect one lead to the B terminal of the switch and the other lead to any of the other terminals. If you get a steady beep then the switch is bad. If you don't then turn the key to the On position. It should beep when you hit the C terminal or the center post. When you turn to Start you should get a beep on the S terminal. If the switch tests good then the trouble is toward the wiring harness.

John

RetiredBMC
03-19-2017, 02:19 PM
Gents... Just wanted to thank you all again for your help!!! I finally got it fixed....come to find out, I messed up my brand new solenoid when I tighten down the battery and starter cables to the solenoid studs. Making it too tight "fuses" the inside leaving it in an always "on situation". Slapped a new solenoid on with cables just a little snug and the car shuts off when I turn the key to off!!!

Thanks again, I did learn a lot and probably saved alot of money by not having a mechanic come out....lol.
Eric

jopizz
03-19-2017, 02:22 PM
Gents... Just wanted to thank you all again for your help!!! I finally got it fixed....come to find out, I messed up my brand new solenoid when I tighten down the battery and starter cables to the solenoid studs. Making it too tight "fuses" the inside leaving it in an always "on situation". Slapped a new solenoid on with cables just a little snug and the car shuts off when I turn the key to off!!!

Thanks again, I did learn a lot and probably saved alot of money by not having a mechanic come out....lol.
Eric

I've never seen that happen before but then again the new parts are made much more cheaply than the original parts. Glad to hear that you got it fixed without having to tear into the wiring.

John