Operator Panel Displays All Diamonds, Five Beeps - Lexmark C540n Service Manual

Operator panel displays all diamonds, five beeps

Step Questions / actions
1 Turn the printer off, and remove the rear
shield. See "Top cover assembly removal"
on page 4-13.
Turn the printer on, and verify the following
values at JOPP1:
Pin
1
2
3
4
5
6
7
Are all these values approximately correct?
Check for continuity in the operator panel
2
cable connector.
Note: Remove the three screws holding the
operator panel, and place it facedown on top of
the printer. The cable connector pins will be
exposed and easier to contact.
Do all the conductors indicate continuity?
JOPP1
Value
0 V dc
+5 V dc
0 V dc
Ground
+5 V dc
+3.3 V dc
Ground
Yes
Go to step 2.
Replace the operator panel.
See "Operator panel logo
plate" on page 4-9.
5025-2xx, 4xx
No
Replace the controller
board. See "Controller
board removal" on
page 4-20.
Replace the front cover
assembly. See "Front
cover assembly removal"
on page 4-2.
2-37
Diagnostic information