7085 Message indicates load paper in tray 3

[PaperCut]

konica 7085, Paper tray 3 will not unlock/open. Message display indicates "load paper in tray 3". Although unable to unlock tray 3, I am able to see paper in tray 3 drawer when tray 2 is open. (1st and 2nd tray is working fine)

So far I swap the Door sensor, solenoid for locking system on the tray , lift up motor. on the 2nd tray, put it on the 3rd tray. just to see if this all working fine. But it's all good. SO I change the main control board and still same problem.

Any Idea whats wrong.

[aidil rashidi]

try checking all the actuator at the paper detect assy...(the black plastic actuator beside the paper supply roller)..one more thing is the connector at the back side of tray 3 properly connected to the connector on the main body?