My experience of flying various types from three major manufacturers is that helicopters with a single hydraulic system have the facility for the pilot to revert to manual control. Those with two separate hydraulic systems do not have manual reversion and the design is such that both systems cannot be simultaneously switched off.
I have been told by an engineer working on the type that there is no manual reversion on the 169 and it is not possible to switch off both systems at the same time.