Setting the outside temp. Not a remote on smart gear

Place your remote temperature sensor and the inside unit together for about an hour to see if they both read the same or if there is a large difference in the temperatures.

Dashes on the outside temperature reading may indicate that the inside unit is not receiving a signal from the remote. Change the batteries on the remote or change the location of the inside and/or outside units so that they can receive a strong signal between each other.

Your smartphone temperature may be coming from a location that is not near your home. They are often from a weather service. Where is your local temperature sensor located? Is it in the sun? Is it on the south side of the house, or another location where the sun or an air conditioner or other heat source may affect the accuracy of the reading? Try to locate your outside sensor in a shaded location with plenty of ventilation, and away from heat sources.

battery or internal damage

https://www.manualslib.com/manual/841274/Jlr-Gear-Smart-Gear.html

Bring outside temp sensor indoors. Remove batteries from both remote and base. replace outside first with fresh batteries (Alkaline recommended). Then the base. Make sure they are on the same channel. When display restored, you can take the remote back outside.

Check manual for calibration

try seeking assistance from hobbyist stores that sells parts for mini RC cars, they often sell gears to help upgrade their RC cars, you might find a gear that fits your needs.

You have to push some buttons to tell the MAIN unit to scan, then put battery into the REMOTE, set channel, and hit reset through a little hole. And the MAIN should see it.

Hold the button down on your remote and then press and immediately release the smart/learn button. Do this for each remote.

Press and immediately release the smart/learn button and then walk over to your keypad and key in your 4 digit code and press enter.

The key to this is to immediately release the smart/learn button. If you hold it in you will erase what you just did. If you still have a problem please post back.

Start the vehcle and let it warm up then set all the controls to heater? Then turn off the car. Use the remote start to start the vehicle and check the controls are still set to heat mode.