Dc Power Service Check - Lexmark C752 Service Manual

Step Actions and questions
6 Low voltage power supply - Turn the power off and
disconnect the LVPS at J35 on the system board.
Measure the voltages on J35-3 and J35-4. The voltage
should measure approximately +5 V dc.
Is there approximately +5 V dc on any of these
connector pins?

DC power service check

The machine is partially operative, a motor turns, display is on or the Power On LED may be on or off.
Step Actions and questions
1 Does the printer beep 5 times and the operator panel
display all diamonds?
2 DC power to system board - Turn the power off and
disconnect the LVPS cable to J35 on the system board.
Turn the power on and check the following voltages on
the LVPS cable:
J35-1 +3.3 V dc
J35-2 +3.3 V dc
J35-3 +5 V dc
J35-4 +5 V dc
J35-5 +24 V dc
J35-6 +24 V dc
J35-7 +24 V dc
J35-8 +3.3V dc
J35-9 Ground
J35-10 Ground
J35-11 Ground
J35-12 Ground
J35-13 Ground
J35-14 Ground
J35-15 Ground
J35-16 Ground
Note: All voltages are approximate values.
Are the voltages correct?
3
Unplug all cables from the system board, except J6,
J35, J37. See "System board - non-network" on
page 5-6 or "System board - network" on page
Does the printer power up and display a message?
Yes
Replace the
"System board"
on page 4-67
Yes
Go to "Operator
panel LCD/
status LED/
buttons service
check" on
page 2-122
Go to step 3
Go to step 4
5-7.
Diagnostic information
5060-2XX
No
Replace the
"LVPS
assembly" on
page 4-42
No
Go to step 2
Replace the
"LVPS
assembly" on
page 4-42
Replace the
"System board"
on page 4-67.
2-105