DTC P0005: High Pressure Lock-Off Solenoid Control Circuit: Description
WARNING: This page is about a different car, the 2003 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
An ignition voltage is supplied to the High Pressure Lock-Off (HPL) solenoid through the AF Lock-Off fuse. The PCM controls the HPL solenoid by grounding the control circuit via an internal switch called a driver. The primary function of the driver is to supply the ground for the controlled component. The PCM monitors the status of the driver. If the PCM detects an incorrect voltage for the commanded state of the driver, DTC P0005 sets.