John deere 6200se fwd reverse safety switch

On the 6200SE, a no-start that only happens with the FWD/REV lever out of neutral is almost always the neutral start (transmission safety) switch itself, not the seat or park brake circuit.

Most likely causes, ranked:

1. Neutral start switch out of adjustment or worn. This switch mounts on the FNR lever linkage/quadrant and tells the ECU/starter relay the transmission is in neutral. Wear in the linkage or the switch plunger lets the lever "read" as in-gear even when it's centered, or the detent for neutral has shifted so true neutral no longer lines up with the switch's sensing point. Check: with key on, wiggle the lever through neutral slowly and watch for a start-enable signal (test light or multimeter across the switch leads) as you pass through. If continuity only appears in a narrow band that doesn't match where the lever actually sits detented, the switch or its bracket needs adjustment or replacement.

2. Corroded or broken wiring/connector at the switch. These sit low on the console and take moisture and oil mist over the years. Backprobe the connector for voltage drop under load rather than just visual inspection, corrosion inside the pins often looks fine externally.

3. Failed switch contacts internally (mechanically fine, electrically dead). Bypass-test: with the lever confirmed in neutral, jumper the switch connector momentarily to see if the machine cranks. If it does, the switch is confirmed bad, replace it.

4. Less likely: a starter relay or ECU input fault downstream, but this usually throws a code on these tractors rather than a clean lever-position-dependent no-start.

Start with the switch adjustment and continuity check, that resolves this complaint on 6200 series most often. If you can post whether it cranks at all in true neutral, that narrows it further.