– 119 –
TROUBLESHOOTING
2.3 U4
Step
Check
Remedy
YES
NO
1
(Initial Check)
Are any parts broken, malformed, incorrectly installed
or different from those listed in the specifications?
• Principle Parts to be Checked:
(1) Fuser assembly, (2) MCU PWB,
(3) LVPS assembly
2
(Check the thermistor in the fuser assembly.) *1
Does the problem occur soon after the power is turned
ON?
3
(Check that power is supplied to the heater rod in the
fuser assembly.)
When the fuser assembly is cold, does the heater rod
light up when the power is turned ON?
4
Does the problem occur while the fuser is warming up? *2
5
(Check that power is supplied to the heater rod.) *2, *3
For 100V models:
Is a voltage between 90 and 132
VAC supplied between P/J114-
2PIN
↔
P/J114-3PIN?
For 220V models:
Is a voltage between 198 and 264
VAC supplied between P/J114-
2PIN
↔
P/J114-3PIN?
• Measure the voltage while the fuser is warming up
before the U4 error occurs.
6
After the fuser has finished warming up, does the
heater rod turn on and off (light up and go off)? *2
7
(Check the LVPS assembly.) *3
Is a voltage of 4.38VDC supplied between J11-3PIN
↔
J11-6PIN?
8
(Check the ON signal for the heater rod.) *2, *3
Is the voltage 0VDC between P/J11-3PIN
↔
P/J11-6PIN
while the fuser is warming up, and is the voltage
between 0VDC and 4.38VDC after the fuser has
finished warming up?
*1: Since the fuser takes a short time to warm up, determine whether the problem occurs soon after warming up.
*2: To determine whether the fuser is warming up properly, check the operation of the main motor and check
whether the heater rod is turned on or off.
*3: Do not touch the HVPS or any other high voltage components when disconnecting P/J12 from the MCU PWB.
Replace the part or
install the part
correctly.
See step 2.
See section 3.6
Faulty Thermistor.
See step 3.
See step 4.
See section 3.5
Faulty Heater Rod.
See step 5.
See step 6.
See section 3.6
Faulty Thermistor.
See step 7.
See step 8.
Replace the LVPS
assembly.
Replace the LVPS
assembly.
Replace the MCU
PWB.
See section 3.6
Faulty Thermistor.
Replace the LVPS
assembly.
Содержание WinType 4000
Страница 1: ...WinType 4000 TECHNICAL MANUAL SECOND EDITION LASER PRINTER ...
Страница 4: ......
Страница 6: ... 2 GENERAL SPECIFICATIONS ...
Страница 14: ... 10 THEORY OF OPERATION ...
Страница 26: ... 22 THEORY OF OPERATION Figure 2 9 Electrical ...
Страница 28: ... 24 REPLACEMENT AND ADJUSTMENT OF PARTS ...
Страница 62: ... 58 REPLACEMENT AND ADJUSTMENT OF PARTS ...
Страница 64: ... 60 MAINTENANCE GUIDE ...
Страница 111: ... 107 MAINTENANCE GUIDE Direction the paper is fed through the printer H G F 3 Skew 2 0mm E 2 0mm E F G H 245mm ...
Страница 114: ... 110 MAINTENANCE GUIDE ...
Страница 116: ... 112 TROUBLESHOOTING ...
Страница 176: ... 172 5 ELECTRICAL 5 1 Disassembly Drawing 1 2 3 4 14 4 14 2 14 1 14 3 13 12 11 6 5 7 8 9 10 ...
Страница 179: ......