How to Wire a Ford Solenoid

by Russell Wood

A Ford starter solenoid is one of the key components to the starting system of most older Ford vehicles. It's essentially a big relay, which provides power from the battery to the starter motor when the ignition key is turned over, starting the vehicle. These solenoids are typically the first thing that goes out when a Ford engine won't turn over and are easy to replace. Wiring them from scratch isn't difficult either, but it does take a little bit of time.

1

Run a section of 4-gauge cable from the positive terminal on the battery to the "A" post on the side of the solenoid. Then run a section of 4-gauge cable from the "A" post on the side of the solenoid to the "BATT" terminal on the starter motor. Strip 1/2 inch of shielding off each end of the cable using the wire strippers and then crimp the terminals on both ends using the battery terminal crimper. Then connect the wires to the battery, starter and solenoid using the open-end wrench set.

2

Run a section of 18-gauge wire from the "B" terminal on the solenoid to the "S" terminal on the starter motor. Strip 1/4 inch of wire from the end of the wire using the wire strippers and then crimp a blue ring terminal on each end. Then connect the wiring to the terminals using the open-end wrench set.

3

Run a section of 18-gauge wire from the "S" terminal on the top of the solenoid to underneath the steering column on the interior of the vehicle. Probe the wiring underneath the column using the 12-volt test light. Turn the ignition to the "on" position. If you find a wire that lights up the test light, then turn off the ignition. If the light turns on and off with the ignition key, then you've found an ignition source. Crimp the blue Scotchlok connector onto the ignition wire and the wire connecting to the solenoid using the needle-nose pliers, then crimp a blue ring terminal onto the other end of the wire and connect it to the solenoid using the open-end wrench set.

4

Run a section of 18-gauge wire from the "I" terminal on the starter to the "+" terminal on the ignition coil. Strip 1/4 inch of wire from the end of the wire using the wire strippers and then crimp a blue ring terminal on each end. Then connect the wiring to the terminals using the open-end wrench set.

Items you will need

About the Author

Russell Wood is a writer and photographer who attended Arizona State University. He has been building custom cars and trucks since 1994, including several cover vehicles. In 2000 Wood started a career as a writer, and since then he has dedicated his business to writing and photographing cars and trucks, as well as helping people learn more about how vehicles work.

Photo Credits

  • photo_camera Nicolas Agustin Cabrera/Demand Media