Diagnostics information 2-23
Cooling fan service check Cover interlock switch service check
Note: Make sure a print cartridge assembly is installed and the cover closes all the way, engaging the cover
open switch lever.
LVPS/HVPS Verify main power to controller board
With the printer off, unplug the LPS/HVPS cable at J502 on the controller board. Verify
grounds on pins 10, 12, 14, 16 and 18 for both the cable and the controller board. If any of
these grounds are incorrect, then check the cable for continuity. If the cable fails continuity,
then call the next level of support.
Turn the printer on with the cable still unplugged, and verify the following on the cable
(controller board will not be powered):
If any of the voltages are incorrect, then replace the LVPS/HVPS. See “Dead machine
service check” on page 2-24.
FRU Action
Cooling fan Make sure the fan cable plug is properly seated at J9 (controller board).
Turn the printer on. Within a few seconds, the controller board assembly should apply
+24Vdc to pin2.
If voltage is not present, then check or replace the controller board. See “Controller
board removal” on page 4-6.
If voltage is present, then check pin 1 for 24 V dc as well. If it is close to 24 V dc while
the fan is still idle, then replace the fan. See “Fan removal” on page 4-16.
FRU Action
Cover interlock switch Disconnect the cover interlock cable from the controller board at J7.
With the printer turned off:
1.Verify continuity be tween cable pin 1 and pin 2 with the door closed and discontinuity
with the door open.
2.Verify conti nuity between cable pin 1 and pin 3 with the door open and discontinuity with
the door closed.
3.Verify disconti nuity between cable pins 2 and 3 whether the door is open or closed.
If any fail, then replace the cover interlock switch.
If both pass continuity, then turn the printer on, and measure +5 V dc on pin 2 at J7 on
the controller board.
Verify pin 3 at J7 is ground.
If voltage or ground is not present, then see “Controller board service check” on
page 2-22 for more information.
Controller board service check (Continued)
FRU Action
Pins Voltage
6, 17, 19 +24 V dc
1, 3-5, 11, 13,
15 +5 V dc