Structure And Operation: PPMU
WARNING: This page is about a different car, the 2012 Infiniti QX56 and 2011 Infiniti QX56. However, it is still accessible from the selected car via links, so may be relevant.
- PPMU stands for Passive Pressure Maintenance Unit.
- System pressure increases according to increase of oil volume due to oil temperature increase. Sudden rise in system pressure can be controlled by feeding the increased oil into the PPMU.
- Oil flows into oil chamber via PPMU pipe A and PPMU pipe B by influence of pressure change, pushes gas spring of nitrogen gas, and pools.
When system pressure decreases, influent oil is distributed to both pipes by gas spring reaction force of nitrogen gas via PPMU pipe A and PPMU pipe B to control sudden decrease in system pressure.