Pentair IChlor 30 Temperature Guage Not Working

I'm getting the flashing red light that according to the manual means an issue with the flow/temperature gauge. When I try to get the temperature it shows -- F which obviouslky means it needs to be replaced. Question is should the SWG function when this is gauge is not working? Mine is not generating any chlorine so I'm hoping the answer is no and that this is the issue. Pretty sure I can fix it myself.
 
The SWG cannot calculate the salt level with an inoperative temperature sensor and will not run.

They are easy to replace.

iChlor Flow-Temperature Switch Replacement Kit (P/N 523100) has a black nut. The IntelliChlor flow switch replacement (P/N 520736) has a thicker grey nut that will not fit properly in the iChlor.

See the INTELLICHLOR AND iCHLOR FLOW-TEMPERATURE SWITCH REPLACEMENT KIT Installation Guide