LVPS service check
Action Yes No
Step 1
Check if the power supply cable is properly connected to the controller
board.
Is it properly connected?
Go to step 2. Reseat the cables.
Step 2
a Turn off the printer.
b Remove the power cord.
c Measure the resistance between terminals A and D of the power
supply socket.
Is the resistance approximately 30 ohms?
Contact your next level
of support.
Replace the power
supply. See “Power
supply removal” on
page 223.
Toner density sensor service check
Action Yes No
Step 1
Remove the transfer roll, and check for loose toner blocking the toner
density sensor.
Is it free of loose toner?
Go to step 2. Clean the sensor.
Step 2
Check the toner density sensor for proper operation:
a Lower the ACM assembly.
b Move the toner density sensor wiper from left to right.
Does it move freely?
Go to step 3. Reinstall the wiper
properly. If it still
cannot move freely,
replace the toner
density sensor. See
“Toner density sensor
removal” on page
232.
Step 3
Check the toner density sensor cable for proper connection to the
controller board.
Is it properly connected?
Go to step 4. Reseat the cable.
Step 4
Check the toner density sensor cable for damage and pinch points.
Is it free of damage?
Replace the controller
board. See “Controller
board removals” on
page 184.
Replace the toner
density sensor. See
“Toner density sensor
removal” on page
232.
4514-630, -635, -636
Diagnostic information
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