Just picked up a really clean and well maintained 500 XC SP 45th Anniversary Edition with a couple issues -- the temp light is always lit dimly, the coolant temp gauge doesn't work, and as a result it's running in limp mode. Unplug the connector on top of the head, and the temp light goes off and it runs normal.

Replaced the sensor with a new OEM one, same issue persists. The next connector in line up against the bulkhead is connected and the terminals are clean. What's the next step in diagnosing this issue?

Thanks in advance; any suggestions are appreciated.