what wires go to the starter solenoid

On most ATV solenoids, the two large terminals are for battery positive and starter motor. The small terminals are for the trigger wire from the key switch and a ground. Usually the red small wire goes to the trigger (S terminal), black small wire to ground. But double-check your model. I've seen Polaris use a slightly different layout. Look up the part number on the solenoid and confirm with a multimeter.

I just did this on a similar Polaris. The large terminal closest to the battery positive cable goes to the starter. The other large terminal connects to the battery positive. For the small terminals, one is the activation wire from the start button (usually red), the other is a ground. Some solenoids have a cap or diagram printed on them. Check for markings like S, I, B, M.

Be careful not to mix up the small wires. If you put the ground on the trigger terminal, it might just click and not crank. Use a test light to find which small wire gets 12V when you press the start button. That one goes to the S terminal. The other small terminal gets a constant ground or is connected to the frame.

I believe on the Sportsman 500, the red small wire comes from the ignition switch and the black goes to the chassis ground. But verify the wire colors against a wiring diagram. Also, the large terminals: one is from battery, one to starter. If you reverse them, it still works because it's just a switch, but polarity doesn't matter on a solenoid coil? Actually the coil is polarity-sensitive in some designs. Stick to manufacturer specs.

I've seen solenoids where the small terminals are labeled with letters. 'S' stands for start signal, 'I' for ignition (bypass), 'B' for battery, 'M' for motor. If yours has no markings, the typical setup is: one small terminal is the activation, the other is ground. The big terminals are usually interchangeable except in old Ford-style solenoids where one is specifically for battery.

Don't guess—use a multimeter. Measure resistance: the two large terminals should show continuity when the solenoid is activated. The small terminals should show a coil resistance between them (typically 10-50 ohms). Identify which small wire is hot when starting, then connect it to one small terminal. The other small terminal goes to ground. That's how I sorted mine out.

I disagree with the idea that large terminals are interchangeable. On some solenoids, the built-in diode or resistor requires a specific orientation. I had a solenoid that fried because I swapped the large cables. So definitely check the datasheet or service manual. For a Sportsman 500, the battery cable goes to the terminal that also connects to the start switch internally.

I'm a mechanic and deal with these all the time. Simple rule: the two large terminals are for the battery positive (B+) and the starter (M). The small terminals: one gets 12V from the start button (S), the other is ground (G). If your solenoid has an extra small terminal, it might be an ignition bypass (I). That one gets 12V only during cranking to boost the ignition coil.

On my '06 Sportsman, the red wire went to the solenoid terminal that had a 'S' cast into the plastic. The black wire went to the one marked 'G' (ground). The large cables: one from battery (marked B) and one to starter (marked M). If yours is unmarked, look up the OEM part number online, sometimes they have a diagram.

I used a cheap automotive solenoid once, and the terminals weren't marked. I just wired it by trial with a fused wire. I connected the small wires to the two small terminals arbitrarily, and it worked. But I read some solenoids have a polarity-sensitive coil, so if it doesn't click, swap them. Also make sure your battery is fully charged.

One more thing: the battery negative cable should go to the engine block or frame, not to the solenoid ground terminal. The solenoid's ground terminal is just for the control circuit. So make sure your black small wire actually goes to a good chassis ground. Some solenoids are internally grounded, so you might not need an external ground wire at all.

I'd recommend getting a service manual for your specific model. There are free PDFs online. The wiring diagram will show exactly which wire goes where. For the Sportsman 500, the solenoid has four terminals: two large and two small. The small ones are for the start enable relay (often a red wire) and the ground (black). The large: battery positive to one, starter cable to the other.

You might also check the solenoid itself. Some have tiny letters stamped near the terminals. If not, use a continuity tester between the small terminals and the large ones. Usually, one small terminal has continuity to one of the large terminals when the solenoid is off (that's the 'S' terminal that connects to the coil). The other small terminal is isolated.

I rebuilt my 500 last year. I found that the solenoid I bought from Amazon came with a diagram sticker. If yours didn't, search for 'Polaris Sportsman 500 solenoid wiring diagram' on YouTube. There are a bunch of videos showing exactly which wires go where. Saved me a lot of guesswork.

A word of caution: if you get the large cables wrong, you could short the battery to ground when you press start. Some solenoids have the battery terminal isolated from the mounting bracket, others don't. I always disconnect the battery before messing with the solenoid. Then I use a multimeter to check for continuity between the large terminals and the bracket.

On my ATV, the small wires were both the same color (white). I had to trace them back to the start button and the key switch. The one from the start button was hot only when pressing start, the other from the key switch was hot when the key was on (for the ignition bypass). So if both small wires are red/black, they might be different circuits. Use a test light.

I'd just buy an OEM solenoid that comes with a wiring diagram or at least has labeled terminals. Aftermarket ones can be inconsistent. I wasted an afternoon because the cheap one I got had the small terminals swapped relative to the original. The engine only clicked until I swapped the small wires.

Another tip: sometimes the ground wire for the solenoid isn't a wire but a metal tab that bolts to the frame. If your solenoid has a mounting stud, that might be the ground. Then the two small terminals are both signal: one from the start button and one from the safety switch (like neutral or brake). Check if your ATV has a neutral safety switch.

I think the simplest method: connect the battery positive cable to one large terminal. Then connect a jumper wire from that same large terminal to one small terminal. When you turn the key and press start, if the solenoid clicks, you've got the right small terminal. If not, swap the jumper to the other small terminal. Once it clicks, you know the activation terminal. Then connect the red wire there and the black to ground. That's how I bench-tested mine.

I had a similar issue on a different brand. I eventually learned that the small wires are actually part of the start interlock circuit. If your ATV has a brake lever switch or a tether switch, one of the small wires might be from that. So don't assume one is always ground. Trace the wires back to their sources. A wiring diagram is your best friend here.