Lexmark C750 Service Manual page 167

Step Action and questions
7 RIP board—measure the voltage at connector J1-2 on
the RIP board. See
voltage measures approximately +5 V dc.
Is the voltage correct?
8 Operator panel cable (operator panel connection)—
make sure the operator panel cable is seated correctly
in the connector on the operator panel board.
Is the cable seated correctly?
9 Operator panel cable—check continuity of the operator
panel cable.
Is there continuity?
10 RIP board—a poor ground connection between pin 4
on the operator panel board connector can cause this
symptom. Check for continuity between Pin J1-4 and
ground on the board. See
Is there continuity?
11 Operator panel cable—check continuity of the operator
panel cable.
Is there continuity?
12 Operator panel assembly—does the operator panel
display all diamonds, with the power on/status LED on
and 5 beeps?
13 Voltage checks at RIP connector J1. See
on page 5-14. Check the voltages on RIP connector J1
as shown:
Pin Voltage
(display static)
J1-1 +5 V dc
J1-2 +5 V dc
J1-3 +5 V dc
J1-4 Ground
J1-5 +5 V dc
Are the voltages correct?
14 Operator panel cable—check continuity of the operator
panel cable.
Is there continuity?
"RIP board" on page 5-14. The
"RIP board" on page
"RIP board"
Voltage (display active—LCD
Test running)
Voltage varies 1.0 to 2.0 V dc
+5 V dc
Voltage varies 1.0 to 2.4 V dc
Ground
+5 V dc
Yes
Replace the
operator panel.
See "Operator
panel removal"
on page 4-46
Go to step 9
Replace the RIP
board. See "RIP
board removal"
on page 4-70
Go to step 11
5-14.
Replace the
operator panel.
See "Operator
panel removal"
on page 4-46
Go to step 13
Replace the
operator panel.
See "Operator
panel removal"
on page 4-46
Replace the
operator panel.
See "Operator
panel removal"
on page 4-46
Diagnostic information
5060-00x
No
Go to step 8
Seat the cable
correctly
Go to "Operator
panel removal"
on page 4-46 and
replace the
operator panel
cable
Replace the RIP
board. See "RIP
board removal"
on page 4-70
Go to "Operator
panel removal"
on page 4-46 and
replace the
operator panel
cable
Call your next level
support
Go to step 14
Go to "Operator
panel removal"
on page 4-46 and
replace the
operator panel
cable
2-133