The contact owns a 2016 Chevrolet Volt. The contact stated that while the vehicle was parked, the check engine warning light illuminated. The contact used a scanner and retrieved DTC: U2603-U2606 and U2607-U2622. The dealer was made aware of the failure. The vehicle was scheduled for an upcoming diagnostic test. The vehicle was not yet diagnosed or repaired by an independent mechanic or the dealer. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 95,000.