Lexmark Optra S Service Manual - Page 131

4059-XXX Serial Port Service Check Run the "Serial Wrap Test" on page 3-12. Note: The Serial Wrap Test is designed to check the serial port hardware by using a wrap plug (P/N 1329048) and invoking the Serial Post Diagnostic Test. The test helps isolate the printer from the serial cable and host. The test provides failure information on the display for approximately three seconds. If the test indicates a problem, replace the controller board. Toner Sensor Service Check Service Tip: Check the print darkness MENU setting before checking the toner sensor. This service check is intended to be used when a 929 Service Error displays. FRU 1 Developer Drive Assembly 2 Toner Sensor Cable Action Incorrect operation of the developer drive assembly can cause the printer to display a 929 error code (Toner Sensor). Check the developer drive assembly for correct installation, any sign of worn, loose or broken parts. Check the toner sensor assembly cable to make sure it is properly seated into the toner sensor. If correct at both the sensor and engine board (J10), check the continuity of the cable. If incorrect, replace the cable. Diagnostic Information 2-104