[Joerod]

My '89 302 H.O. Mustang set up for 10 years, so I got it out and readied it for cranking. After new oil, priming oil pump. cleaning gas tank. cleaning all ground connections, etc. I was ready to crank. By accident I had mounted the battery + cable to the post on the solenoid with the starter motor cable. When I touched the battery (-) cable to the battery post I got a big arc. No smoking wires. Seeing what I'd done, I switched the the battery (+) cable to the other post on the solenoid where it should have been. I checked the fusible links below the solenoid and they all looked good. Turned the ignition switch and there was no response, ie., no dash lights. headlights. fuel door release. fuel pump. To start troubleshooting the electrical system I'd appreciate any suggestions from anyone who is knowledgeable with this problem on a 1989 Mustang.

Joerod

[T-bucket23]

Check all the battery cables to start with and move out from there. All your mistake should have done was engage the starter.

A bad connection will become worse as soon as you try to draw current through it. Dig out your meter or test light and start tracing

[75gmck25]

As T-bucket23 said, your error would have just caused the starter to turn over. There was a big arc because its a high current draw.

Connect the cables to the solenoid and try to activate the starter by applying 12 volts to the start terminal on the solenoid. If that works then you have power to the vehicle and the starter.

Then start following the wiring that runs up to the fuse box and recheck the fusible links. You could also use a section of 10 gauge or larger wire to run a temporary connection from the battery + up to the fuse box, which would bypass all the existing wiring. I'd also put a 30 amp fuse holder in the temp wire, just in case you have a short to ground somewhere else in the wiring.

If bypassing the wiring gets you power to turn the car on, then start rechecking each section of wire and each fusible link. If bypassing it does not work, then you need to start looking at the fuse box and the fuses.

Bruce

[Joerod]

T Bucket & 75 GM:

Thanks for the tips. Doing what both of you suggested and found starter motor still good. Viasually inspected ignition switch and found it looking o.k.
Solenoid switch checks o.k. Going to start testing the fusible links below the battery box, especially the 10 ga yellow to the ignition switch, and then go on from there. Visually the fusible links appear good. Should they show signs that the smaller wire and the insulation have melted?

Joerod

[T-bucket23]

Originally Posted by Joerod

T Bucket & 75 GM:

Thanks for the tips. Doing what both of you suggested and found starter motor still good. Viasually inspected ignition switch and found it looking o.k.
Solenoid switch checks o.k. Going to start testing the fusible links below the battery box, especially the 10 ga yellow to the ignition switch, and then go on from there. Visually the fusible links appear good. Should they show signs that the smaller wire and the insulation have melted?

Joerod

You need to use a meter, visual inspection of electrical components is usless

[Joerod]

T-bucket:

Going to use test light. continuity tester and VOM to check the circuits. Hoping the damage was restricted to the fusible links which are easy to reach below the solenoid switch. Got to wait on some warmer weather as no heat available in shop right now. Temps 20-30 degree range.

Joerod