Highlights
- GM bulletin PIT6534A covers 2027 Corvette coupes and convertibles that lose Wi-Fi, navigation or OnStar connected services.
- The fault doesn’t clear when the car is shut off and restarted.
- Engineers are still investigating. Dealers have a temporary module reset in the meantime.
- An earlier version of the bulletin listed 10 other 2027 GM models.
General Motors has sent dealers a preliminary service bulletin for 2027 Corvette coupes and convertibles that lose connectivity tied to the OnStar module, as first reported by GM Authority. According to bulletin PIT6534A, owners may find the Wi-Fi hotspot dead, the navigation display frozen or OnStar connected services unavailable. The condition is not intermittent, and restarting the car won’t clear it. GM engineers have not yet found the cause.
The Corvette isn’t alone. GM Authority reported in September that the original PIT6534 bulletin also covered the 2027 Buick Enclave, Cadillac Lyriq, Optiq and Vistiq, Chevrolet Blazer EV, Equinox, Equinox EV and Traverse, and GMC Acadia and Terrain. Columnist Eric Starkman pointed out that GM’s guidance warns an OnStar emergency call may not go through if a crash happens while the system is offline.
What Dealers Are Doing About It
For now, technicians are told to reset the Telematics Communication Interface Control Module (TCICM), which runs OnStar, GPS and the Wi-Fi hotspot. The procedure involves removing the module and backup battery cover, disconnecting the backup battery and waiting five minutes before reinstalling it. Once all diagnostic trouble codes are cleared, a green light next to the OnStar button at startup means the module is back online. GM notes the problem may return, and the car would then need another reset.
Every 2027 Corvette is still within Chevrolet’s 3-year/36,000-mile bumper-to-bumper warranty. Owners who notice a missing OnStar status light, a frozen map or a dead hotspot should visit a dealer and mention the bulletin number. This is a preliminary bulletin and not a recall, so owners shouldn’t expect a notice in the mail.
A Long Year for GM Connectivity
Telematics faults have followed GM through most of 2026. In January, GM Authority reported that owners of the Blazer EV, Equinox EV and Cadillac Lyriq, among others, were losing navigation, OnStar and Super Cruise, and some were waiting on backordered replacement modules. In July, bulletin PIT6529A blamed a software anomaly in the K73 telematics control module for intermittent connectivity loss that could correct itself. The Corvette’s issue doesn’t, and it comes about a week and a half after GM recalled certain 2027 Grand Sport models to replace an incorrect emissions label.
Source: GM Authority
