Our Beta 38 temperature Guage stopped working. 

 We removed the wire from the sensor and grounded it to the block.

We have tried grounding the wire from the sensor to the block, the Guage jumped up to100 so it seems the guage is working. 

 We removed the plug on the back of the Guage and reconnected it on the electrical panel. 

 We started the motor and ran it for over 10 min and the Guage did not move. We felt the expansion tank and the antifreeze was hot. So that seems to me to say the thermostat is working and the antifreeze is moving.

 There is a but connector coming out of the tubing by the the sensor that has no wire on the other end. However there is only one wire connected to the sensor with no broken of connector so I think maybe it was not used?

Any help would be apricated.

Couldn't be the sensor? 

Thanks,

s/v Elegant'sea Chip & Debbie