Mobile data is working as far as I can tell. LTE and 4 bars displayed in the upper right hand corner of the device. My zip code where I live is 95901, and within close proximity is 95991 and 95993. I can be in and out of those three zip codes in 20 mins.
Hwy. 20 runs through zip codes 95901 and 95991. Hwy 99 intersects hwy 20 in Yuba City CA. Taking hwy 99 south puts me in zip code 95993. If I take bridge St. From Marysville CA into Yuba City CA bridge St intersects with hwy 99. So traveling that way the zip codes would be as follows. 95901, 95993, and then 95991. Going the other way would be. 95901, 95991, and then 95993.