Techniques provided herein are directed toward using information from various sources to determine when the mobile device enters and exits a traffic tunnel, turning off the GNSS receiver of the mobile device when the mobile device enters the tunnel, and turning the GNSS receiver back on once it exits. For example, the mobile device can turn off the GNSS receiver based, at least in part, on a determination that the mobile device has entered the traffic tunnel, and a determined traffic tunnel length and/or estimated amount of time the mobile device will be in the traffic tunnel.