Starting car from starter relay

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jysnflem

jysnflem

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Like the title says I can't start the car under the hood using a jumper wire at the starter relay. Over the years I've been able to do this with no problems, but have probably not done it in a couple of years. I had my engine out this winter and was trying to get it started at the relay but no success. Using the ignition switch to start it works fine. Last year changed the wiring to MAD ELECTRICAL update with fuseible wire links drove all summer no problems. Something to note this spring when trying to start from the relay I did accidently ground the jumper wire to the header for a brief moment which did spark. Car still starts from the ignition switch just not at the relay. I did swap the relay for a new one and still no luck. What do you think? Jayson
 
The car should crank when you jumper the two obvious bare terminals, IE the big battery stud and the "big square" starter terminal

However, if you do that, with the key on, you will be "going through" the ballast resistor if you use one, so the spark won't be as strong as it might be. Might help to jumper a right to the coil + terminal until it fires.
 
Forgot to add car is using MSD ignition without ballast ressitor long before I did the MAD ELECTRICAL update. Jayson
 
So it cranks but won't fire, or won't crank? You DID turn the key on?
 
Woops forgot to mention that. From the starter relay it doesn't crank, but cranks and fires when using the ignition switch. Thanks for the help. Jayson
 
Which jumper wire did you accidentally ground?

Are you doing this?
1. Turning on the ignition switch
2. Then going under the hood and jumpering from Batt + to the start terminal on the starter relay? Or are you jumpering to the starter solenoid wire coming from the starter relay? We need to know what you are jumpering to where....

It is not making sense that it starts from the key switch but you cannot get it to crank by puting batt + to the start solenoid; the key switch sends the + to the solenoid via the relay... But....Is this a manual trans, and what year?
 
So I turn the ignition switch on and then go under the hood where I put the alligator clip to the big battery stud and then would take the other end of the jumper wire to the black wire with the screw and square post. When I accidiently grounded the one end of the alligator clip it was only connected to the big battery stud and the other end fell down to the header sparking for a moment. Thanks for help. Jayson
 
Well, connecting the big stud to the square stud ought to do it; that is what the relay does when the ignition switch it turned to 'start'.....I suspect your jumper was blown open when it contacted the header and sparked; the battery was trying to push, oh, about 300-400 amps through it! Try another jumper and see that happens.
 
A screwdriver is the best jumper I have used.
 
nm9stheham said:
well, connecting the big stud to the square stud ought to do it; that is what the relay does when the ignition switch it turned to 'start'.....i suspect your jumper was blown open when it contacted the header and sparked; the battery was trying to push, oh, about 300-400 amps through it! Try another jumper and see that happens.
Click to expand...

this
 
The ignition switch sends 12 volts on the yellow wire to signal the start relay.
 
Thanks guys I'll try a new jumper wire. Jayson
 
I just took a meter to the jumper wire to measure itsOhm's and it has nothing. Looks like you're right. Jayson
 
I assume you mean infinite ohms, not near 0.....Sucks when your tools let you down! Well, at least it was not hard, and you have a spare relay now....! The screwdriver is easy to visually inspect for '0 ohms'....LOL.
 
This whole issue really was a brain fart moment. When I thought about it I just couldn't figure out what wire burned up due to the spark when using my jumper wire. LOL. Thanks for the help everyone. Jayson
 
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