Lexmark C912 Service Manual - Page 162

5055-xxx Hardware tests LCD Hardware Test The LCD Hardware Test causes the printer to continually execute the LCD display test. To cancel the test, press Return or Stop. Button Test The Button Test verifies the operation of each button on the operator panel. When Button Test is selected, the following appears on the display: OP OP OP OP OP OP When a button is pressed, CL (Closed) displays. When a button is not pressed, OP (Open) displays. If the wrong message displays, the button is malfunctioning. To exit the button test, press Return or Stop. DRAM Memory Test The DRAM Memory Test checks the validity of DRAM (both standard and optional). Patterns of data are written to DRAM verifying each bit in memory can be set and read correctly. When selecting this test from the operator panel, the printer begins testing DRAM memory and the following message is displayed: DRAM Memory Test P:##### F:##### Terminology: P:###### represents the number of times the memory test finishes successfully. Initially 000000 displays for ######. The maximum pass count is 999,999. F:##### represents the number of times the memory test finishes with errors. Initially 00000 displays for #####. The maximum fail count is 99,999. 3-12 Service Manual