Nosewheel stops working after I start taxiing

[LancyVancy]

I do everything to make the nosewheel work, it then works flawlessly, but stops working after I taxi for about 5 seconds. This is accompanied by a warning sound.

What am I doing wrong here?

[Mark Amber]

When this happened to me I assumed I broke the gear or something on landing or mis configured a system. I was having almost no hydraulic pressure. 
 

I never found out what it was that caused the pressure to fall what error or omission I made or if it was a bug, but I did not have the issue again. Try a hard landing on the nose gear or simulating a failure of the hydraulics and see if the symptoms match. Maybe I will take the Saab 340 for a flight today and see.