DOWNLOAD Sharp MX-6500N / MX-7500N (serv.man21) Service Manual ↓ Size: 561.77 KB | Pages: 66 in PDF or view online for FREE

Model
MX-6500N MX-7500N (serv.man21)
Pages
66
Size
561.77 KB
Type
PDF
Document
Service Manual
Brand
Device
Copying Equipment / Section 7 Troubleshooting
File
mx-6500n-mx-7500n-sm21.pdf
Date

Sharp MX-6500N / MX-7500N (serv.man21) Service Manual ▷ View online

MX-7500N  TROUBLESHOOTING  7 – 37
 
H4-30
Upper main thermistor differential 
input abnormality (TH_UM)
 
H4-31
Lower main thermistor differential 
input abnormality (TH_LM1)
 
H4-32
Upper sub thermistor differential input
abnormality (TH_US1)
 
H5-01
5 times continuous POD1 not-reach
jam
 
H7-10
Recovery error from low fuser temp.
(TH_UM_AD2)
Trouble content
The values of TH_UM_AD1 and TH_UM_AD2 do not 
exceed the specified value within the specified time 
from turning ON the HL_UM.
Detail
PCU
Cause
HL_UM does not turn on.
Thermistor trouble.
Harness trouble.
PCU PWB trouble
Check & Remedy
Use SIM05-02 to check the flashing operation of the 
heater lamp.
When the heater lamp flashes normally, check the 
thermistor and its harness.
Check the thermistor input circuit section of the PCU 
PWB.
When the lamp does not light up, check for 
disconnection in the heater lamp and breakage of 
the thermostat.
Check the interlock switch.
Check the lamp control circuit of the AC PWB and 
the PCU PWB.
Use SIM14 to cancel the trouble.
Trouble content
The lower main compensation thermistor and the 
lower main differential thermistor do not exceed the 
specified value within the specified time from turning 
ON the lower main heater lamp.
Detail
PCU
Cause
The lower main heater lamp does not turn ON. 
Thermistor breakdown, harness trouble, PCU PWB 
trouble
Check & Remedy
Use SIM05-02 to check the flashing operation of the 
heater lamp.
When the heater lamp flashes normally, check the 
thermistor and its harness.
Check the thermistor input circuit section of the PCU 
PWB.
When the lamp does not light up, check for 
disconnection in the heater lamp and breakage of the 
thermostat.
Check the interlock switch.
Check the lamp control circuit of the AC PWB and the 
PCU PWB.
Use SIM14 to cancel the trouble.
Trouble content
The upper sub compensation thermistor and the 
upper sub differential thermistor do not exceed the 
specified value within the specified time from turning 
ON the upper sub heater lamp.
Detail
PCU
Cause
The upper sub heater lamp does not turn ON. 
Thermistor breakdown, harness trouble, PCU PWB 
trouble
Check & Remedy
Use SIM05-02 to check the flashing operation of the 
heater lamp.
When the heater lamp flashes normally, check the 
thermistor and its harness.
Check the thermistor input circuit section of the PCU 
PWB.
When the lamp does not light up, check for 
disconnection in the heater lamp and breakage of the 
thermostat.
Check the interlock switch.
Check the lamp control circuit of the AC PWB and the 
PCU PWB.
Use SIM14 to cancel the trouble.
Trouble content
Detail
PCU
Cause
A fusing jam is not canceled completely. (A jam paper 
remains.)
POD1 sensor trouble
Fusing unit installation trouble
POD1 sensor connector and harness connection 
trouble
PCU PWB trouble
Fusing unit, drive section trouble
Check & Remedy
Replace the POD1 sensor.
Check installation of the fusing unit.
Replace the fusing unit.
Check or repair the fusing drive section.
Check connection of the POD1 sensor connector and 
the harness.
Replace the PCU PWB.
Use SIM14 to cancel the trouble.
Trouble content
The fusing temperature does not reach the specified 
level within the specified time from stopping a job due 
to fall in the fusing temperature.
Detail
PCU
Cause
Thermistor trouble.
Heater lamp trouble.
PCU PWB trouble.
Thermostat trouble.
Connector, harness connection trouble.
HL control PWB trouble.
Power unit trouble.
Check & Remedy
Replace the thermistor.
Replace the heater lamp.
Replace the PCU PWB.
Replace the thermostat.
Check connection of the connector and the harness.
Replace the HL control PWB.
Replace the power unit.
Use SIM5-2 to check the flashing operation of the 
heater lamp.
MX-7500N  TROUBLESHOOTING  7 – 38
 
H7-11
Recovery error from low fuser temp.
(TH_LM)
 
L1-00
Scanner feed trouble
 
L2-11
Lamp cooling fan motor trouble
 
L3-00
Scanner return trouble
 
L4-02
Paper feed motor trouble
 
L4-03
Fusing motor trouble
 
L4-06
Transfer unit lift trouble
 
L4-07
Transfer belt motor trouble
Trouble content
The fusing temperature does not reach the specified 
level within the specified time from stopping a job due 
to fall in the fusing temperature.
Detail
PCU
Cause
Thermistor trouble.
Heater lamp trouble.
PCU PWB trouble.
Thermostat trouble.
Connector, harness connection trouble.
HL control PWB trouble.
Power unit trouble.
Check & Remedy
Replace the thermistor.
Replace the heater lamp.
Replace the PCU PWB.
Replace the thermostat.
Check connection of the connector and the harness.
Replace the HL control PWB.
Replace the power unit.
Use SIM5-2 to check the flashing operation of the 
heater lamp.
Trouble content
Scanner feed is not completed within the specified 
time.
Detail
SCU
Cause
Scanner unit trouble.
SCU PWB trouble.
Scanner control PWB trouble.
Harness and connector connection trouble.
Scanner home position sensor trouble.
Scanner motor trouble.
Check & Remedy
Use SIM1-1 to check the scan operation.
Replace the scanner unit.
Replace the SCU PWB.
Check connection of the connectors and the harness.
Replace the scanner home position sensor.
Replace the scanner motor.
Trouble content
A lock signal is detected during rotation of the fan.
A non-lock state is detected except when in rotation 
for booting.
Detail
SCU
Cause
Fan motor trouble.
Harness related to the fan motor
Circuit trouble
Check & Remedy
Check the fan motor related circuits (SCN-Mother 
PWB, SCNcnt PWB) and their harnesses and 
connectors.
Trouble content
Scanner return is not completed within the specified 
time.
Detail
SCU
Cause
Scanner unit trouble
SCU PWB trouble
Scanner control PWB trouble
Harness and connector connection trouble
Scanner home position sensor trouble
Scanner motor trouble
Check & Remedy
Use SIM1-1 to check the scan operation.
Replace the scanner unit.
Replace the SCU PWB.
Check connection of the connectors and the harness.
Replace the scanner home position sensor.
Replace the scanner motor.
Trouble content
A lock signal is not detected within the specified time 
in ON operation of the paper feed motor after 
warming-up or canceling a jam.
Detail
PCU
Cause
Paper feed motor trouble
Paper feed motor harness and connector connection 
trouble
PCU PWB trouble
Check & Remedy
Use SIM6-1 to check the operation of the paper feed 
motor.
Replace the paper feed motor.
Check connection of the paper feed motor harness 
and the connector.
Replace the PCU PWB.
Trouble content
The motor lock signal is detected during rotation of the 
fusing motor.
Detail
PCU
Cause
Fusing motor trouble
Fusing motor harness and connector connection 
trouble
PCU PWB trouble
Check & Remedy
Use SIM6-1 to check the operation of the fusing 
motor.
Replace the Fusing motor.
Check connection of the fusing motor harness and the 
connection.
Replace the PCU PWB.
Trouble content
A change in the primary transfer position sensor 
cannot be detected within the specified time in lifting 
operation of the primary transfer unit.
Detail
PCU
Cause
Transfer unit position sensor trouble
Dirt on the transfer unit position sensor.
PCU PWB trouble
Connection trouble of the connector and the harness.
Transfer unit lift mechanism trouble
Primary transfer belt unit is not installed.
Check & Remedy
Use SIM6-3 to check the separating operation of the 
transfer unit.
Install the primary transfer belt unit.
Replace the transfer unit position sensor.
Clean the transfer unit position sensor.
Replace the PCU PWB.
Check connection of the connector and the harness.
Repair the transfer unit lift mechanism.
Trouble content
The motor lock signal is detected during rotation of the 
transfer belt motor.
Detail
PCU
Cause
Transfer belt trouble.
Harness/connector trouble between the PCU PWB 
and the transfer belt motor.
Control PWB trouble.
Circuit trouble.
Check & Remedy
Use SIM25-1 to check the operation of the transfer 
belt motor.
Check the harness and the connector between the 
PCU PWB and the transfer belt motor.
MX-7500N  TROUBLESHOOTING  7 – 39
 
L4-08
Waste toner transport motor lock
 
L4-16
Fusing pressure release trouble
 
L4-17
Drum motor lock trouble (K)
 
L4-18
Drum motor lock trouble (C)
 
L4-19
Drum motor lock trouble (M)
 
L4-20
Drum motor lock trouble (Y)
 
L4-25
2nd transfer belt motor trouble
 
L4-28
Sub power source cooling fan motor
Trouble content
The waste toner lock sensor is detected during 
rotation of the drum motor.
Detail
PCU
Cause
Waste toner transport motor trouble.
Waste toner transport pipe clogging
Harness/connector trouble between the PCU PWB 
and the waste toner transport motor.
Check & Remedy
Use SIM6-1 to check the operation of the waste toner 
transport motor (WTM).
Check the waste toner transport pipe for clogging.
Check the harness and the connector between the 
PCU PWB and the waste toner transport motor.
Trouble content
A change in the fusing pressure release sensor signal 
cannot be detected within the specified time after 
outputting the fusing pressure release motor.
Detail
PCU
Cause
Fusing pressure release sensor trouble.
Fusing pressure release motor trouble.
Pressure release drive gear and pressure release idle 
gear trouble.
PCU PWB trouble.
Connection trouble of the connector and the harness.
Check & Remedy
Replace the fusing pressure release sensor.
Replace the fusing pressure release motor.
Replace the pressure release drive gear and the 
pressure release idle gear.
Replace the PCU PWB.
Check connection of the connector and the harness.
Trouble content
The motor lock signal is detected during rotation of the 
drum motor (K).
Detail
PCU
Cause
Drum motor trouble
Harness connection trouble between the PCU PWB 
and the drum motor
Control circuit trouble
Check & Remedy
Use SIM25-01 to check the operation of the drum 
motor.
Check the harness and the connector between the 
PCU PWB and the developing motor.
Replace the PCU PWB. Replace the drum motor.
Trouble content
The motor lock signal is detected during rotation of the 
drum motor (C).
Detail
PCU
Cause
Drum motor trouble
Harness connection trouble between the PCU PWB 
and the drum motor
Control circuit trouble
Check & Remedy
Use SIM25-01 to check the operation of the drum 
motor.
Check the harness and the connector between the 
PCU PWB and the developing motor.
Replace the PCU PWB. Replace the drum motor.
Trouble content
The motor lock signal is detected during rotation of the 
drum motor (M).
Detail
PCU
Cause
Drum motor trouble
Harness connection trouble between the PCU PWB 
and the drum motor
Control circuit trouble
Check & Remedy
Use SIM25-01 to check the operation of the drum 
motor.
Check the harness and the connector between the 
PCU PWB and the developing motor.
Replace the PCU PWB. Replace the drum motor.
Trouble content
The motor lock signal is detected during rotation of the 
drum motor (Y).
Detail
PCU
Cause
Drum motor trouble
Harness connection trouble between the PCU PWB 
and the drum motor
Control circuit trouble
Check & Remedy
Use SIM25-01 to check the operation of the drum 
motor.
Check the harness and the connector between the 
PCU PWB and the developing motor.
Replace the PCU PWB. Replace the drum motor.
Trouble content
The motor lock signal is detected during rotation of the 
2nd transfer belt motor.
Detail
MFP
Cause
2nd transfer belt motor trouble
Harness and connector connection trouble between 
PCU PWB and 2nd transfer belt motor
Control circuit trouble
Check & Remedy
Use SIM25-1 to check the operation of the 2nd trans-
fer belt motor.
Check the 2nd transfer belt motor, and replace if nec-
essary.
Check connection of the harness and connectors of 
the 2nd transfer belt motor, and replace if necessary.
Check the PCU PWB, and replace if necessary.
Trouble content
The motor lock signal is detected during rotation of the 
sub power cooling fan motor. 
Detail
MFP
Cause
Fan motor trouble, controller PWB trouble, SCN-
Mother PWB trouble, fan motor/SCN-Mother PWB 
harness connection trouble, controller PWB/SCN-
Mother PWB connection trouble, control circuit trouble
Check & Remedy
Use SIM06-02 to check the operation of the fan motor.
Check the controller PWB, the SCN-Mother PWB, and 
the harness and the connector between the fan motor 
and the SCN-Mother PWB.
MX-7500N  TROUBLESHOOTING  7 – 40
 
L4-30
Controller fan motor
 
L4-31
Paper exit cooling fan F trouble
 
L4-32
Power source cooling fan 1 trouble
 
L4-34
LSU cooling fan trouble
 
L4-35
Paper exit exhaust fan trouble
 
L4-36
Fusing cooling fan trouble
 
L4-39
Machine ventilation fan (R)
 
L4-40
Ozone fan motor 1 trouble
 
L4-41
Ozone fan motor 2 trouble
 
L4-42
Ozone fan motor 3 trouble
Trouble content
The motor lock signal is detected during rotation of the 
controller fan motor.
Detail
MFP
Cause
Fan motor trouble, controller PWB trouble, SCN-
Mother PWB trouble, fan motor/SCN-Mother PWB 
harness connection trouble, controller PWB/SCN-
Mother PWB connection trouble, control circuit trouble
Check & Remedy
Use SIM06-02 to check the operation of the fan motor.
Check the controller PWB, the SCN-Mother PWB, and 
the harness and the connector between the fan motor 
and the SCN-Mother PWB.
Trouble content
The fan operation signal is not detected within the 
specified time in the paper exit cooling fan F 
operation.
Detail
PCU
Cause
The fan does not rotate because of disconnection of 
the fan connector or other trouble.
Check & Remedy
Check the harness and the connector between the 
PCU PWB and the fan.
Use SIM6-2 to check that the fan is actually rotating.
Trouble content
The fan operation signal is not detected within the 
specified time in the power cooling fan 1 operation.
Detail
PCU
Cause
The fan does not rotate because of disconnection of 
the ozone exhaust fan or other trouble. 
Check & Remedy
Check the harness and the connector between the 
PCU PWB and the fan.
Use SIM6-2 to check that the fan is actually rotating.
Trouble content
Detail
PCU
Cause
When the LSU cooling fan is operated, the fan 
operation signal is not detected within the specified 
time.
LSU fan trouble.
Harness, connector trouble.
LSU control PWB trouble.
Check & Remedy
Use SIM6-2 to check the fan operation.
Check the LSU fan, and replace if necessary.
Check the harness/connector, and replace if 
necessary.
Check the LSU control PWB, and replace if 
necessary.
Trouble content
When the fan is operated, the fan operation signal is 
not detected within the specified time.
Detail
PCU
Cause
The fan does not rotate because of disconnection of 
the fan connector or other trouble.
Check & Remedy
Check the harness and the connector between the 
PCU PWB and the fan.
Use SIM6-2 to check that the fan is actually rotating.
Trouble content
When the fan is operated, the fan operation signal is 
not detected within the specified time.
Detail
PCU
Cause
The fan does not rotate because of disconnection of 
the fan connector or other trouble.
Check & Remedy
Check the harness and the connector between the 
PCU PWB and the fan.
Use SIM6-2 to check that the fan is actually rotating.
Trouble content
When the fan is operated, the fan operation signal is 
not detected within the specified time.
Detail
PCU
Cause
The fan does not rotate because of disconnection of 
the fan connector or other trouble.
Check & Remedy
Check the harness and the connector between the 
PCU PWB and the fan.
Use SIM6-2 to check that the fan is actually rotating.
Trouble content
The lock signal is detected during rotation of the 
ozone fan motor 1.
Detail
PCU
Cause
Harness/connector trouble between the PCU PWB 
and the fan motor.
PCU PWB trouble.
Fan motor trouble.
The fan does not rotate because of the other trouble. 
(No power supply to the fan motor) 
Check & Remedy
Use SIM6-2 to check the operation of the fan motor.
Check the harness and the connector between the 
PCU PWB and the fan motor.
Replace the PCU PWB.
Replace the fan motor.
Trouble content
The lock signal is detected during rotation of the 
ozone fan motor 2.
Detail
PCU
Cause
Harness/connector trouble between the PCU PWB 
and the fan motor.
PCU PWB trouble.
Fan motor trouble.
The fan does not rotate because of the other trouble. 
(No power supply to the fan motor) 
Check & Remedy
Use SIM6-2 to check the operation of the fan motor.
Check the harness and the connector between the 
PCU PWB and the fan motor.
Replace the PCU PWB.
Replace the fan motor.
Trouble content
When the fan is operated, the fan operation signal is 
not detected within the specified time.
Detail
PCU
Cause
The fan does not rotate because of disconnection of 
the fan connector or other trouble.
Check & Remedy
Check the harness and the connector between the 
PCU PWB and the fan.
Use SIM6-2 to check that the fan is actually rotating.
Page of 66
Display

Click on the first or last page to see other MX-6500N / MX-7500N (serv.man21) service manuals if exist.