Cooling Fan Service Check; Cover Interlock Switch Service Check - Lexmark E250DN - Govt Laser 30PPM Special Build Mono Taa Service Manual

4512-220, -230
Controller card service check (Continued)
FRU
LVPS/HVPS

Cooling fan service check

FRU
Cooling fan

Cover interlock switch service check

Note: Make sure a toner cartridge assembly is installed and the cover closes all the way, engaging the cover
open switch lever.
FRU
Cover interlock switch
2-40
Lexmark™ E250d and E250dn
Action
Verify main power to controller card
With the printer off, unplug the LPS/HVPS cable at J19 on the controller card. Verify
grounds on pins 7, 12, and 14 for both the cable and the controller card. If any of these
grounds are incorrect, check the cable for continuity. Replace the cable or the respective
card as necessary.
Turn the printer on with the cable still unplugged, and verify the following on the cable
(controller card will not be powered):
If any of the voltages are incorrect, replace the LVPS/HVPS. See
check" on page 2-41.
Action
Make sure the fan cable plug is properly seated at J4 (controller card).
Turn the printer off, and disconnect the cooling fan cable from the controller card.
Turn the printer on. Within a few seconds, the controller card assembly should apply
+24 V dc to pin 2.
• If voltage is present and the fan is not turning, replace the cooling fan. If the fan still
doesn't function, replace the controller card.
• If voltage is not present, check the controller card.
Action
Disconnect the cover interlock cable from the controller card at J6.
With the printer turned off, verify continuity between cable pin 1 and pin 2 with the door
closed and discontinuity with the door open.
Verify continuity between cable pin 1 and pin 3 with the door open and discontinuity with the
door closed.
Verify discontinuity between cable pins 2 and 3 whether the door is open or closed.
• If either fails, replace the cover interlock switch.
• If both pass continuity, turn the printer on, and measure +5 V dc on pin 2 at J6 on the
controller card.
• Verify pin 3 at J6 is ground.
• If voltage or ground is not present, see
for more information.
Pins Voltage
J19-8 +24 V dc
J19-9 +24 V dc
J19-13 +5 V dc
"Controller card service check" on page 2-39
"Dead machine service