If the watch is faulty and still under warranty then you can return it to Garmin for exchange:
STEP 1: Contact Garmin Technical Support to receive an RMA number.Call or e-mail Garmin Technical Support Specialists to describe the problem you are experiencing and request a Return Material Authorization (RMA) tracking number. You will need to provide the unit's serial number (if applicable), your return shipping address, and a daytime telephone number.
Phone: 1 800 235 822
STEP 2: Ship the unit, along with the RMA number, to Garmin.Once you have received the RMA number, securely package the unit and ship it (insured) to the following address:
Garmin Australasia30 Clay PlaceRMA Number: (insert your RMA number here - see above)Eastern Creek, NSW 2766