Lexmark C950 Service Manual - Page 307

5058-030 To perform the Button Test: 1. From the Diagnostics Menu, navigate to HARDWARE TESTS. 2. Select Button Test. The LCD displays a graphic of the operator panel buttons that matches the layout of the operator panel buttons. 3. Press any button on the operator panel. Every time a button is pressed, the equivalent button graphic on the LCD appears shaded. When the button is released, the shading is removed. Previous Next DRAM Test The DRAM Test is used to check the validity of both the device's standard and optional DRAM. The test involves writing patterns of data to DRAM to verify that each bit in memory can be set and read correctly. To run the DRAM Test: 1. From the Diagnostics Menu, navigate to HARDWARE TESTS. 2. Select DRAM Test. DRAM Test Testing... appears on the LCD, and then Resetting the Printer appears. The printer automatically performs a POR. Go Back The following type of message appears: DRAM Test 256MB P:###### F:#### • P:###### represents the number of times the memory test has passed and finished successfully. Initially 000000 displays with the maximum pass count being 999,999. • F:##### represents the number of times the memory test has failed and finished with errors. Initially 0000 displays with the maximum fail count being 99,999. Initially only four digits appear, but additional digits appear as needed. To stop this test before completion, turn the printer off. Panel Test After a user chooses this setting, the device automatically executes the operator panel test application which occupies the entire display panel. The test application automatically toggles each pixel in the display panel through every contrast level, beginning with the darkest (every pixel turned on and as dark as possible) and ending with the lightest (every pixel turned off). The panel then illuminates the backlight, and then it turns off. Essentially, this test identifies any non-functioning pixels, since these appear as blank spaces during the test's darker stages. This test is run by navigating to HARDWARE TESTS and then selecting Panel Test. Serial Wrap 1 Test The Serial Wrap Test is used to check the operation of the serial port hardware using a wrap plug. Each serial signal is tested. INPUT TRAY TESTS Feed Tests (Input Tray) This test is used to observe the paper path of media as it passes through the printer. To observe the paper path, a user can open the upper rear door while this test executes. No information is printed on the feed test pages since the printhead LED isn't engaged during this test. Diagnostic aids 3-19