My braun thermoscan 6022, gives POS or HI readings. Switching on/off and keeping at ambient temp does not work. batteries OK. Worked well for the last 8 yrs, love it, hate to change.

SOURCE: how to change batteries in

push down the small button directly above the battery door with a pen or something slender, while pushing the battery door downward, away from the thermometer. the 6012 model uses two CR2032 button cells.

SOURCE: I have a Braun Thermoscan

... call Braun ThermoScan customer service at 1-800-327-7226

SOURCE: I have a Braun thermoscan type 6022, but code po5

It's not po5, its pos... you're not positioning it properly in the ear canal.

SOURCE: Can you change the temp

Turn off the thermometer
Press and Hold the L/O Button
Continue to hold the start button when the F or C display appears. Watch for these displays to cycle over the display window.
#
Release the start button when the F display appears on the screen.
#
5

Listen for a beep and watch for the Braun ThermoScan ear thermometer to shut itself off, indicating that you changed the temperature scale to Fahrenheit successfully.
#
6

Follow the same procedure but release the start button when C shows on the display to switch from Fahrenheit to Celsius.

SOURCE: We have the Braun 6022

If you whish to switch from Celsius to Fahrenheit, proceed as follows:

(1) Make sure the thermometer is turned off.

(2) Press and hold down the Start button (IRT 4020)
or the «I/O» button (IRT 4520). After about
3 seconds the display will show this sequence:
«°F» / «SET» / «°C» / «SET» ...

(3) Release the Start button / «I/O» button when the
desired temperature scale is shown. There will be
a short beep to confirm the new setting, then the
thermometer is turned off automatically.