Possible Causes

WARNING: This page is about a different car, the 2002 Mazda 626 and 2001 Mazda 626. However, it is still accessible from the selected car via links, so may be relevant.

Following items are possible causes for DTC P0745:

Pressure control solenoid malfunction.
Open or short to ground or power in pressure control solenoid circuits between PCM and pressure control solenoid.
Damaged connectors or wiring harness between pressure control solenoid and PCM.
PCM malfunction.