John Deere 6320 temperature sensors

If the fuel thermal sensor is unplugged from the harness and a bolt been placed in the thermostat housing, will this show a tractor to be running hot? I just bought a 6320, after it runs for 10-12 min the temp light and blue round i light turns on, plus the temp needle goes from cold to red hot within a second when the lights comes on. I can turn the switch off-on without stopping the engine and lights and gauges clear up for another 10-12 min.
While replacing the coolant temperature sensor I noticed an extra "male" wiring plug. This harness isn't used and I only have one sensor in the thermostat housing.
Any advice on this extra plug or why the warning lights come on?
I did plug my old coolant temperature sensor in the "extra"harness ( just let it hang outside the engine) and let the tractor idle for 30 min. No warning lights nor did the needle move, any! I unplugged the old sensor from the extra harness and the warning lights came on and needle pegged hot after 10 min idle. Plugged the sensor back in and warning lights went off needle went back to cold.
I did shoot the engine in several locations with a thermal gun after idling for 30 min with warning lights on. I was getting readings between 95-125*.

I don't know anything about a 6320 thermal sensor, but I have experience with the air temp sensor on my Kaw 4010 mule. In the summer the computer sends too much fuel to engine and it idles like crap. I bought a kaw service manual.
Ran every test, did a computer scan and everything is within factory specks.

As a last resort, I decide to replace the theromister with a fixed resister with less resistance making the computer think the air was a little warmer. It worked. After playing around trying to make a theromister the resistance I wanted, I finally put OEM thermosister in place and wired another 10K thermosister in parallel with it.

Engine now runs better, idles better and plugs are cleaner than when it was new. I could tell when it was new my fuel/air mix was rich, plugs were a little carboned.

Good luck with your temp sensor problem. I've heard of a guy who has similiar issues with his van. He hung a new water temp sensor beside his engine and it worked better.

I know you always run a risk damaging an engine when you play around tricking the computer. How is that any different than when we play around adjusting the fuel mix screw on a carb?
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