How do I clear the WSO100 outside temperature offset using Maretron’s DSM150 or DSM250 display?

You clear the WSO100 outside temperature offset using Maretron’s DSM150 or DSM250 display in the following way:

1. Enter menu mode, scroll to "Configuration…" and press 
2. Scroll to "Device Configuration…" and press 
3. Scroll to the row containing the WSO100 and press 
4. Scroll to "Restore Factory Defaults" and press  twice.

Beware that resetting factory defaults resets all settings back to factory defaults, not just the outside temperature.