You would want to lock your Xoom SIM card in order to protect your Xoom from any unwanted access, especially if it is lost or stolen.
Ensure a SIM card is inserted, and follow these tip below to enable this function:
1. Hit Xoom’s Home button.
2. Locate the Apps icon on your Homescreen and tap on it.
3. Next, select Settings .
4. Then tap on Location & security option.
5. Next choose Set up SIM card lock.
7. Now, put a checkmark on Lock SIM Card.
8. Provide the correct SIM PIN (4-8 digits).
The default PIN code is 1111.
9. Next, select OK.
10. You will need to verify your PIN again and tap OK to end the process.