Lexmark T620 Service Manual - Page 113

4069-5XX/7XX Main Drive Service Check Service Tip: Excessive gear or main drive assembly noise is usually caused by a defective motor assembly or system board. Service Tip: If there are equally spaced horizontal lines across the page, go to "Print Quality - Evenly spaced horizontal lines or marks." on page 2-113. WARNING: Whenever the gearbox assembly is removed from the machine it must be handled very carefully. Do not allow any of the gears to come in contact with any metal or other hard surface to avoid gear damage. It is also very important not to let any dirt, paper, staples or other material come intact with the grease in the gearbox assembly. FRU 1 Main Drive Assembly (Excessive noise or vibration) 2 Main Drive Motor Assembly (Excessive noise, gears ratcheting and so on) 3 Main Drive Motor Cable Action Remove the system board and run a Diagnostic Print Test in the continuous mode. Check the main drive assembly for any excessive noise or vibration. Determine if the noise is in the main drive, toner cartridge, fuser or main drive gearbox. Look for any loose or worn parts in the developer drive assembly, main drive gearbox or fuser. Repair as necessary. A service error code 936 - Transport Motor may be displayed. Check the voltage at J27-6 on the system board. It measures approximately +5 V dc when the motor is not running and goes to 0 V dc when the motor is running. If incorrect, replace the system board. If this does not fix the problem, replace the main drive motor. Check the continuity of the main drive motor cable. If incorrect, replace the cable. Diagnostic Information 2-85