My ws-9002u thermometer outside reading doesn't display,but inside does.what is problem?

I have a recurring problem with a GE Profile PSB48LSRABV. Here's an example sequence:

• Fresh food compartment set to 37F on the control panel (for months)
• Thermometer in fridge reads 46F (with lots of water inside per manual)
• Press "Display Temp" button, display shows fridge at 37F
• Turn power off, count to 15, turn power on, wait for control panel to boot
• Press "Display Temp" button, display shows fridge at 46F (matches thermometer!)
• Compressor runs and cools fresh food compartment
• Hours later thermometer in fridge reads 37-38 (yeah!)
• Press "Display Temp" button shows fridge at 37F
• Within days, the fridge is warmer inside again, thermometer inside reads 45+, but display reads 37 - unit needs to be "rebooted" again!

Fresh food thermistor from top of cabinet measured properly in ice water (and warmer water), the unit has always passed all the self-tests, and condensor coils and fan are clean, so I had techs come give it a shot under home warranty:

• Trip 1 - Tech came to assess, ordered new evaporator fan
• Trip 2 - Replaced fresh food evaporator fan (note new fan is working in fridge, and old fan works fine on bench)
• Trip 3 - Ordered main computer PCBA
• Trip 4 - Replaced main computer PCBA

Unfortunately, it continues the same cycle of misreading the temperature until power cycles, and taking a day off of work for each visit is getting painful.
Any ideas?

Question edited for clarity. Full 'make model (what it is)'.

Did you put batteries in both units and in the right order, sensor first?

Step 1: Insert 2 fresh AA, batteries into the TX29U-IT sensor according to the polarity marked in the battery compartment.

Step 2: Insert 2 fresh AAA, Alkaline batteries into the wireless thermometer according to the polarity markings. Step 3: After 5 minutes place sensor outside in a shaded location.

https://www.lacrossetechnology.com/products/WS-9160U-IT#support

Retired unit so no further warranty or parts.

You can still get one on Amazon

La Crosse Technology WS-9160U-IT Digital Thermometer ...

Amazon.ca https://www.amazon.ca > Technology-WS-9160U-Digita...

Digital thermometer with wireless remote and clock; Remote sensor transmits from up to 330 feet; records daily high and low temperatures; Receives weather ...
Rating: 4.4 · ‎ 7,970 reviews · ‎ $31.50 · ‎ In stock
..

Find your temp settings inside the fridge and adjust. It takes 24 hrs to set to the new settings. If the controls are on the outside like mine then don't believe the display. Get a thermometer and put it inside. I have to keep mine at 42 outside display, any lower and it freezes the milk and veggies.

sound like faulty out side air temperature sensor located center radiator support.

I have a thermometer with an outside sensor. It's necessary to remove both batteries, wait a few minutes, then replace batteries - sensor first. It may take a few minutes for the inside clock to pick up the signal. If it doesn't, try again with new batteries.

My outside display stopped working, but the inside display still worked. I found that one of the two batteries in the inside unit was almost all the way dead. Once I replaced both batteries the outside display worked. I also checked the batteries in the outside unit. After all batteries were installed, I pushed the small button that is inside the battery compartment on the outdoor unit. It's now working perfect..

I have a BIOS wireless indoor/outdoor thermometer. The indoor base unit doesn't display the outdoor temperature - it is blank - however the other temperatures - humidity, indoor temp, etc., are displayed, What is the problem? We have misplaced the manual so we don't know what to do.

I would guess the outside thermometer has lost its calibration.
Does it seem consistently 5, 10 or 20 degrees off all the time?
Let me know.
Regards,

Have you got this solved?

my thermometer is blinking -40 degrees how can i fix this