* Battery Cable (Heavy Gauge): A very thick, heavy-gauge cable connects directly from the positive (+) battery terminal to the solenoid's large terminal (usually the one on the side). This provides the high amperage current needed to crank the starter motor.
* Starter Motor Cable (Heavy Gauge): Another heavy-gauge cable runs from the solenoid's smaller terminal to the starter motor itself. This completes the circuit to spin the starter.
* Ignition Switch Wire (Smaller Gauge): A smaller-gauge wire runs from the ignition switch to the solenoid. This is the "trigger" wire. When you turn the key to the "start" position, this wire sends power to the solenoid, activating it. This wire usually connects to the smaller terminal on the solenoid, often with a spade connector. The exact color of this wire might vary slightly.
* Ground: The starter motor and the solenoid itself are grounded to the engine block. This completes the electrical circuit. You'll want to make sure the engine block has a good ground connection to the chassis.
Important Considerations:
* Diagram: The best way to be absolutely certain is to consult a wiring diagram specific to your 1985 Jeep Grand Wagoneer. A repair manual (like a Haynes or Chilton manual) for your year and model will be invaluable. These diagrams usually show wire colors and locations.
* Safety: Working with the battery and starter system involves high voltage and amperage. Always disconnect the negative (-) battery terminal before working on any of this wiring. Failure to do so could result in serious injury or damage.
* Corrosion: Check all connections for corrosion. Clean them thoroughly with a wire brush and apply dielectric grease to prevent future corrosion.
Without a wiring diagram specifically for your vehicle, this is the most general information possible. A wiring diagram is crucial for accurate identification.
