I would recommend reaching out to Marathon directly for assistance in operating your Slim-Jumbo Atomic Digital Wall Clock. Their contact information is linked below:
https://www.marathonwatch.com/pages/contact-us
This clock's default timezone is Eastern (E), so when you reset the clock it goes back to the default. To change the timezone, press and hold down the "+" or Up Arrow" button on the back of the clock for three seconds. The clock will beep and you will see a different timezone. Rine and repeat til you get to your desired timezone .
There is a button on the back to change between Celcius & Fahrenheit.
https://www.youtube.com/watch?v=kqXzBKbGlJ8
Best thing to do is reset it to fix it.
This model does not have a light
It will not Illuminated at night. And the information for outdoor temperature is being sent in from the nearest radio tower information. So it will not need to put this outside directly unless you want it out there you can.
The instruction manual can be found here: https://cdn.shopify.com/s/files/1/2581/7358/files/CL030062_UM_EN_FR_20170223.pdf?9881288197653525951
Power
4 x AA Batteries
Here is a link to the user manual.
https://m.media-amazon.com/images/I/A1fOFgQYIRL.pdf