Unitrans is alerting its riders that its popular bus-arrival prediction service will start to degrade as early as next Tuesday, Feb. 22, and go down completely by the end of February, affecting almost all routes.

The outage is expected to last until late April or early May, said Jeff Flynn, general manager of Unitrans, the ASUCD-operated bus system serving the campus and city.

Blame it on AT&T. Blame it on supply chain issues.

The problem has to do with the wireless transmission of GPS location data from Unitrans buses to Cubic Transportation Systems, the company that generates the Umo IQ, formerly Nextbus, arrival time predictions and live route maps showing the movement of individual buses around the campus and city.

Unitrans buses are equipped with Cubic technology that works with AT&T’s 3G cellular network. Starting Feb. 22, however, AT&T will decommission its 3G network in favor of 4G and 5G. And the Cubic equipment now in use on Unitrans buses will not work with the newer networks.

(The arrival prediction service may work sporadically through the end of the month, depending on how quickly AT&T completes its 3G decommissioning work across the city.)

“We’ve been working with Cubic for months to get our equipment upgraded,” Flynn said. “But the parts continue to be unavailable. First, there is a lot of demand, and second, the pandemic has interrupted the supply chain.”

AT&T’s decommissioning of its 3G network will not affect bus-arrival prediction service for two Unitrans lines: A and L. Yolobus is operating those lines temporarily, and Yolobus works with a different company for bus tracking. Can Unitrans switch to a new company? Easier said than done, Flynn explained, because Unitrans would need to acquire new equipment from that company.

Start out early

“We know this outage is a huge inconvenience,” Flynn said, noting that the Unitrans website — where the bus-arrival predictions are posted front and center — gets around 5,000 hits every weekday. The same information is available from UmoIQ.com (or NextBus.com), the UC Davis mobile app and an automated phone line, among other sources.

Until the prediction service returns, Unitrans advises its riders to arrive at their bus stops three to five minutes before the arrival times as stated on the printed and posted schedules for each route. Printed copies are available on the buses, or you can find each route’s schedule on the Unitrans website and other services like Google Maps.

Unitrans customer service support will experience the same lack of real-time bus tracking data as riders. But you can still call customer service at 530-752-2877 for schedule and trip planning support.

“Staff is working hard to try to get the service restored,” Flynn said. “We thank our riders in advance for their patience.”