Thread: New 02 GTP Anniversary Issues

my car had the same problem, was a bad boost solenoid. cost me 20 bucks from the dealership i work at. gauge would only go up halfway and lack of power. mine had set a p1646 in the pcm which did not turn on the MIL, here is the circuit description from the online service manual, Output Driver Modules (ODMs) are used by the PCM to turn on many of the current-driven devices that are needed to control various engine and Transaxle functions. Each ODM is capable of controlling up to 7 separate outputs by applying ground to the device which the PCM is commanding ON. Unlike the Quad Driver Modules (QDMs) used in prior model years, ODMs have the capability of diagnosing each output circuit individually. DTC P1646 set indicates an improper voltage level has been detected on the output circuit which controls the supercharger Boost Control Solenoid.