Lexmark T430 Service Manual - Page 77

4048-1xx Operator panel service check Warning: Never replace both the operator panel and controller card at the same time. Otherwise, some critical settings will be permanently lost. Inspect the operator panel cable for damage. Make sure the cable is plugged in securely. Run POST and check for proper operation. See"Power-On Reset (POR) sequence" on page 2-2. FRU Operator panel Operator panel cable Controller card assembly Action If the buttons do not depress or click when pressed, replace the operator panel. If the operator panel does not illuminate, turn the printer off and unplug J5 on the controller card. Verify pin #4 is ground. Turn the printer on and verify +5 V dc on pins #2 and #5. Also verify +3.3 V dc on pins #6 and #7. • If any of the voltages fail, replace the controller card. See "Controller card assembly removal" on page 4-50. • If all of the voltages are correct, verify the continuity of the operator panel cable. If the cable fails continuity, replace it. See "Operator panel cable removal" on page 4-20. • Otherwise, replace the operator panel. See "Operator panel assembly removal" on page 4-22. If the operator panel display is erratic during POST, replace the following FRUs one at a time in the order shown: • Controller card assembly Note: Always check printhead alignment after replacing the controller card assembly. See "Printhead assembly adjustment" on page 4-2 for hardware alignment of the printhead. • Operator panel • Operator panel cable Diagnostic information 2-43