YILMAZ CA 601 Manual page 27

9.2. Error notices on display
Scraping piston is not at the back (-S3) ;
Insufficient air pressure or Y2 valve may
remain affixed
FIGURE-9
Motor Piston
Ahead Sensor S7
Motor Piston
at back Sensor S4
Scraping sensor is out of order
(-S3) ; Change S3 tearing piston
sensor
Top Tearing Piston
Sensor (-S3)
Motor piston not at the back (-S4) ;
Insufficient air pressure or Y3 valve
may remain affixed