I may have mis-spoke ... That temp channel in the AS T Y looks to be wired to a different pin than the normal temp pin in the xducer cable connector ...
-----
Look under the Setup tab in the Main Menu System for "Select Readouts" ... and see if you have options for "Aux Temperature" and "Water Speed" ...
According to the operators manual ... You can change Readout boxes 1-5 in sonar views ...but can only change Readout Box 1 in Chart views ...
Post back if you don't have Readout Box selections for "Aux Temp" and "Water Speed" ...
It may be a bad AS T Y or temp/speed accessory ...
Also, is the temp/speed accessory you have the TS W ...??
Rickie