P0045 means the engine control module has detected an open circuit in the electrical path that controls the turbocharger or supercharger boost-pressure regulating solenoid. This usually prevents the solenoid from being commanded properly, so the boost-control system cannot modulate turbo/supercharger output as intended.
The solenoid valve itself can fail internally with an open coil or stuck plunger, breaking the commanded circuit and setting the code.
An open, broken, corroded, or disconnected wire or pin in the solenoid harness interrupts the signal or ground path between the PCM and the solenoid.
Leaks, cracks, or disconnections in the vacuum hoses, or a binding wastegate actuator, can prevent proper boost control and may be misread as a circuit issue.
A blown fuse, damaged relay, or weak ground to the boost-control solenoid can cause the circuit to appear open even when the solenoid is good.
A genuinely failed output driver in the PCM is possible but uncommon; it should only be considered after the solenoid, wiring, and power/ground have been verified.
Short trips are usually possible, but the vehicle may be in limp mode with reduced power. Continued driving can strain the turbocharger and reduce performance, so it should be diagnosed soon.
The code itself does not usually damage the turbo, but incorrect boost control from a stuck wastegate or failed solenoid can lead to overboost or underboost conditions that may stress engine components.
Usually no. PCM failure is one of the least likely causes for this code. Most cases are due to a failed boost-control solenoid, wiring fault, or vacuum/actuator issue. The PCM should only be suspected after the circuit and components have been thoroughly tested.
Yes. The diagnostic approach is the same whether the vehicle is turbocharged or supercharged, because the code refers to the boost-control solenoid circuit rather than the compressor itself.