Heidelberg sm52 error code e22 and unit 1 wash up blade not functioning

Hallo all, I wanto to ask abotu error on heidelberg sm52, seveeral days ago on screen appear error code e 22, and unit 1 wash up blade is not fuction.
Here is the pciture, anybody can help?

 

Remove tray and see if sensor is working see if . you can use manual to accurate tray

 

In sm52, there is no sensor for the tray

 

Of course there is.

 

Sorry, I mean the tray in front

 

It is probably the fault of a failed pneumatic directional control valve,

 

I already replace the valve with the new one, but problem is still exist

 

You exchanged the valve, or the piston?

 

You are correct , there is no sensor on the wash up trays , many times my colleague would leave the trays off and the press would still go through the wash up cycle , what a mess , solvent everywhere !!! The press doesn't know if the trays are on or off