Possible Causes
WARNING: This page is about a different car, the 2002 Mazda Millenia and 2001 Mazda Millenia. However, it is still accessible from the selected car via links, so may be relevant.
Following items are possible causes for DTC P0734:
- Low ATF level.
- Deteriorated ATF.
- Shift solenoids "A", "B" and "C" or pressure control solenoid stuck.
- Low line pressure.
- 3-4 clutch, 2-4 brake band slipping.
- 1-2 shift valve, 2-3 shift valve, 3-4 shift valve, pressure regulator valve, pressure modifier valve or solenoid reducing valve stuck.
- Oil pump malfunction.
- PCM malfunction.