gto zp 52 2 color last unit impression issue

when I press production button. The first unit prints the paper however the last unit doesnt. Last unit starts to give impression after 5-6 sheets are printed by 1st unit. Last unit doesn't start printing as soon as it press production button however First unit does. Its a strange problem please guide.

 

Problem likely caused by mechanical wear of roller switch pivoting lever or roller, both are plastic components and tend to wear out over time. You must remove both operator side covers and check condition of these switches, which are mounted on brackets and running on cams bolted to impression cylinder journals. Could also be a failing relay which is triggered by the above mentioned roller switches, but most commonly its the mechanical wear I'd mentioned previously.