I guess you have already gone through your "select readouts" and looked for it. Now, if you have a seperate temp probe, it may not be hook up or come unloose. It could also be your transducer on one of the units if you are sharing. Go through your diagnostics and check making sure everything is connected. Power your unit off and on. Also try under the similator mode. I have found with my 1198 that my depth reading doesn't show until my transducer hits some water. Just a few tips. Good Luck.