Lexmark T620 Service Manual - Page 83

4069-5XX/7XX 230 Paper Jam - Check Duplex message displays. The page is not duplexed and only exits half way out of the redrive. FRU 1 Duplex Stepper Motor Action Check the stepper motor cable for cuts or pinched wiring. Check the routing of the motor leads along the left side of the bottom tray. Check for correct installation of the motor cable connector at J3 on the system board. Check for any shorts between each pin of the motor cable and the motor housing. If shorts are found, replace the motor. Check the resistance of the stepper motor between J3-1 (Stpmtr A-) to J3-2 (Stpmtr A+). The resistance measures approximately 10 ohms. The resistance between J3-3 (Stpmtr B-) to J3-4 (Stpmtr B+) measures approximately 10 ohms. If the resistance is incorrect, replace the stepper motor. Check for shorts between windings on pins J3-1 to J3-2 and pins J3-3 to J3-4. If a short is found, replace the stepper motor assembly. If no short is found, replace the duplex system board. Diagnostic Information 2-55