My Timex WS4 has a blank screen after I changed the battery. May I know what is wrong with it?

SOURCE: Timex Atlantis 100 screen went blank

same thing happened to mine. you might have cracked the inner screen and the only thing i can suggest is to replace it!

SOURCE: can not seem to set my altimeter on the ws4 timex

Setting and Calibrating Your Altitude
1. Press MODE until CAL is shown.
2. Hold SET to begin the calibration.
3. Press START/SPLIT (+) until HOME ALTI is displayed (or choose WEATHER when calibrating weather).
4. Press MODE (NEXT) to begin the setting process.
5. Press START/SPLIT (+) or STOP/RESET (-) to increase or decrease setting values.
6. Set the value to your current elevation.
7. Press MODE (NEXT) to advance to the next setting option.
8. Press SET (DONE) to finish.
9. To complete calibration for the REFRENCE HOME altitude (or WEATHER setting), press and hold STOP/RESET until watch beeps.

Repeat this procedure for WEATHER, making sure to choose the proper weather condition on the WS4 that matches your current weather.

Once these two variables are calibrated, your WS4 will be ready to go, providing you with accurate altitude, pressure, and weather forecast information at your fingertips. Enjoy.