Lexmark T430 Service Manual - Page 70

4048-1xx Service checks Service checks involve measuring voltages of the LVPS, HVPS, and controller card assembly. Continuity and resistance verifications are done on cables and components as required. Note: When looking at the printed side of a printed circuit board, connectors are designated with "J" followed by a number. Pin #1 is designated on the board by an adjacent "1" or triangle. Pin numbers index sequentially to the opposite end of the connector. See "Controller card assembly" on page 5-2 for more information. The controller card passes +5 V dc and +24 V dc from the LVPS to its clients. Therefore, when either voltage is missing as an output on the controller card, be sure to verify the inputs from the LVPS (J17, sockets 1 and 2 at +24 V dc and socket 5 at +5 V dc). Cooling fan service check FRU Cooling fan (fuser) Cooling fan (LVPS) Action Make sure the plugs of the cooling fan cables are properly seated. Both fans are connected to the same +24 V dc on pin #1 at J19 on the controller. Pin #2 is ground for both fans. Therefore if one fan functions and the other does not, either the fan or the cable is faulty. Turn the printer off and disconnect the cooling fan cable at the suspect cooling fan. Turn the printer on. Within approximately 15 seconds the controller card assembly should apply +24V dc to the fan. See "Controller card assembly" on page 5-2 for more information. • If voltage is present, reconnect the fan to verify the fan is faulty. If it is, replace the fan. • If voltage is not present, disconnect the cable from the controller card (J19) and check for continuity on each cable. - If the cable is good, see "Controller card service check" on page 2-38 for more information. - If the cable is damaged, replace the cable. 2-36 Service Manual