One problem related to navigational (global positioning system) gps has been reported for the 2026 GMC Terrain. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2026 GMC Terrain based on all problems reported for the 2026 Terrain.
I have brand new GMC Terrain 2026, I leased dog on Aug 4th 2025. After one week into driving the vehicle, onstar, gps nav stopped working and the emergency calling is not working. All features related to locating the vehicle through onstar or through google stopped working, in addition to sos not working. I took it to the dealership they said the telematics module needs replacement.