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Discussion Starter · #1 ·
Ok, i posted a week or so ago about my ignition problems. took the underdash/underhood alt wiring out of the car and when i put it back in the car, the key will not activate the ignition. when bumping the motor over via the starter relay, it gets really hot and smokes within seconds. As midlife said, there must be alot of amps going through it. Someone suggested taking a voltmeter to the relay to see if it is getting 12 Volts. i am not sure which is which to get 12 volts so i did all of them and hopefully someone on here knows. When checking the post (+) that has the battery cable going to it and the Ignition smaller post, there is approximately 8 volts. + post to Starter post approx 13 volts. Starter post to Ignition post approx 5 volts. + post to - post approx 13 volts. 5 volts between - and Ignition post. No volts between - and Starter post. let me know if it sounds right.
 

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Measure all voltages relative to battery ground. Here's what you should be reading:
Post where battery connects: 12-13V
Second small post: 6-9 V when key is in ON position, 12V when key is in CRANK position
First small Post: 0V when key is in ON Position, 12V when key is in Crank Position
Post where starter connects: 0V at all times except when key is in Crank position.

If your problem of smoking/heating wires occurs only when you are cranking, then your starter must be shorting out. I'd look carefully at the wire going to the starter. If the insulation is good, then the starter must be bad.

If your problem is smoking/heating wires occurs when the key is in the ON position, then you have a problem elsewhere.
 

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It could easily be defective....if the contact area inside is reduced through wear or corrosion or produces excessive resistance, heat is generated.


Solenoids cost very little; Im surprised you didnt just replace it by now.
 

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Discussion Starter · #4 ·
Eureka!!!! i used jumper wires at the connector where the neutral safety switch harness plugs into the underdash harness and Voila! the key works. now, why would it work before i took out the harness and now it doesn't? I will get a new neutral safety switch if have to but i would like to diagnose the one on there cause a new one is around $50! except for alignment (using a pin in the hole to align the switch), what else can i check? thanks for the help!
 

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If it's aligned right and the tranny is in park, two wires should be electrically connected.

If not, best to replace the switch....better than having to rig it on a rainy day!!
 

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::If you do go ahead and replace that starter relay, get one from NAPA, I went through 3 of Autozones relays, Napa's has lasted a year now and no problems. ::
 
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