A320 PTU Fault

[subsonic69]

Hi guys...

Weve been having troubles on one of our aircraft since last week.

Main Problem: PTU FAULT
this aircraft has a habit of generating this message on the EWD after #1 engine start when the #2 engine has stabilized.

we replaced every component in the TSM and B2 guys have already checked their wirings and everything is clean. Unfortunately this problem still exists.

normally the problem goes away when both P/B for #1 & #2 engine driven pumps are off and pressurizing the system using the yellow elec pump after both engines has stabilized. and then turning edp switches to on again after the fault goes away.

ANOTHER one I noticed is that when on ground and you turn on the YELLOW ELEC PUMP, the pressure is only 2100psi. But when you switch the PTU switch to off, the yellow system gives out 3000PSI. But when we turned off the yellow elec pump and i asked a mechanic to open the cargo doors with ptu switch in auto, the system generated 3000PSI. I know the PTU is inihibited during cargo door ops but maybe that is why it generates 3000psi (since the PTU doesnt have to work)

i know it may be the PTU but the other crew before us replaced the new PTU they installed thinking that it was bad from stock (since we replaced everything in the TSM list and problem still exists). thinking of 2 bad from stock PTU is very very rare. but Im open to it.

so I'm asking.

ANY IDEAS or experience with these problems ? and yes its on one aircraft only.

i tried to give as much info so that you can analyze the situation .. HELP!!1

[Fargoo]

Sounds like you have an internal leak in the green system.

Have a look at this task in the TSM TASK 29-23-00-810-812

Since the PTU is already eliminated, looks like a check valve is suspect.

[subsonic69]

fargoo

thanks fargoo..

will try it out ... and give feedback (if we have that part in stock)