Lexmark T620 Service Manual - Page 77

4069-5XX/7XX Cover Open Switch/Cable Service Check FRU 1 Toner Cartridge 2 Cover Open Switch/Cable Assembly Action Check the toner cartridge to make sure it is correctly installed and that the right and left cartridge tracks are not loose or broken. Check to make sure the cover open switch activation tab on the toner cartridge is not broken and that the tab correctly activates the cover open switch spring. Check the cover open switch for proper mechanical operation. If incorrect, repair as necessary. Disconnect the cover open switch cable from J3 at the system board and measure the voltage at J4-3. It measures approximately +5 V dc. If the voltage is incorrect, replace the system board. If the voltage is correct, check the voltage at J3-1. If the voltage measures greater than +1.0 V dc, replace the system board. If the voltage is correct, check the continuity between J3-1 and J3-3 on the cable. If no change in continuity occurs as the switch is activated, replace the cover open switch/cable assembly. If the continuity changes as the switch is activated, replace the system board. Diagnostic Information 2-49