Sharp MX-6500N / MX-7500N (serv.man21) Service Manual ▷ View online
MX-7500N TROUBLESHOOTING 7 – 49
U6-88
EEPROM trouble (2 series)
U6-89
Room temperature thermistor break-
down (2 series)
down (2 series)
U6-90
Room humidity thermistor breakdown
(2 series)
(2 series)
U7-50
MFPC PWB - Vendor machine
communication error
communication error
U7-51
Vendor machine error
U9-01
Touch panel trouble
UC-02
CPT - ASIC error
UC-12
CPT - ASIC abnormal trouble
(DSPF detection)
(DSPF detection)
UC-20
DOCC ASIC error
UC-30
Anti-copy MODULE trouble
(DSPF detection)
(DSPF detection)
UE-10
LCT1 suction fan motor trouble
Trouble content
The EEPROM contents are garbled.
Detail
PCU
Cause
A3 2-stage LCT control PWB trouble
Malfunction caused by noises
Malfunction caused by noises
Check & Remedy
Replace the A3 2-stage LCT control PWB.
Trouble content
Room temperature thermistor open or short
Detail
PCU
Cause
Room temperature thermistor harness connection
trouble
Room temperature thermistor trouble
A3 2-stage LCT control PWB trouble
trouble
Room temperature thermistor trouble
A3 2-stage LCT control PWB trouble
Check & Remedy
Check connection of the harness and the connector of
the room temperature thermistor.
Replace the temperature and humidity sensor.
Check the A3 2-stage LCT control PWB.
the room temperature thermistor.
Replace the temperature and humidity sensor.
Check the A3 2-stage LCT control PWB.
Trouble content
Humidity thermistor open or short
Detail
PCU
Cause
Humidity thermistor harness connection trouble
Humidity thermistor trouble
A3 2-stage LCT control PWB trouble
Humidity thermistor trouble
A3 2-stage LCT control PWB trouble
Check & Remedy
Check connection of the harness and the connector of
the humidity thermistor.
Replace the temperature and humidity sensor.
Check the A3 2-stage LCT control PWB.
the humidity thermistor.
Replace the temperature and humidity sensor.
Check the A3 2-stage LCT control PWB.
Trouble content
Communication error between the MFP and the serial
vendor.
vendor.
Detail
MFP
Cause
Improper setting of the vendor machine specifications
(SIM26-3).
Vendor machine trouble.
MFPC PWB trouble.
Connector, harness connection trouble.
Strong external noises.
(SIM26-3).
Vendor machine trouble.
MFPC PWB trouble.
Connector, harness connection trouble.
Strong external noises.
Check & Remedy
Cancel the error by turning OFF/ON the power.
Check the connector and the harness in the
communication line.
Change the specifications of the vendor machine
(SIM26-3).
Replace the MFPC PWB.
Check the connector and the harness in the
communication line.
Change the specifications of the vendor machine
(SIM26-3).
Replace the MFPC PWB.
Trouble content
Detail
MFP (Notification of a trouble from the serial vendor)
Cause
Serial vendor machine trouble.
Connector, harness connection trouble.
Connector, harness connection trouble.
Check & Remedy
Err.XX is displayed on the operation panel of the
vendor. (XX is the detail code.)
Repair the vendor machine referring to the detail
code.
Check the connector and the harness in the
communication line.
vendor. (XX is the detail code.)
Repair the vendor machine referring to the detail
code.
Check the connector and the harness in the
communication line.
Trouble content
Communication error, Read / Write error, ICU internal
error
error
Detail
SCU
Cause
SCU PWB trouble
Check & Remedy
Check connection signal between the SCU CPU and
the touch panel controller.
the touch panel controller.
Trouble content
Detail
DSPF
Cause
SCU PWB trouble. (CPT-ASIC trouble.)
Check & Remedy
Replace the SCU PWB.
Trouble content
Access abnormality to the CPT - ASIC (when the
ASIC operates abnormally)
ASIC operates abnormally)
Detail
SCU
Cause
B to B connector connection trouble.
DSPF PWB trouble.
CPT - ASIC trouble.
DSPF PWB trouble.
CPT - ASIC trouble.
Check & Remedy
Check the B to B connector.
Replace the DSPF PWB or the Option PWB.
Replace the DSPF PWB or the Option PWB.
Trouble content
Detail
SCU
Cause
SCU PWB trouble. (DOCC-ASIC trouble.)
Check & Remedy
Replace the SCU PWB.
Trouble content
Access abnormality to the DOCC-ASIC (when the
ASIC operates abnormally)
ASIC operates abnormally)
Detail
DSPF
Cause
B to B connector connection trouble.
DSPF PWB trouble.
DOCC-ASIC trouble.
DSPF PWB trouble.
DOCC-ASIC trouble.
Check & Remedy
Check the B to B connector.
Replace the DSPF PWB or the Option PWB.
Replace the DSPF PWB or the Option PWB.
Trouble content
Suction fan motor abnormality
Detail
PCU
Cause
Motor lock
Motor RPM abnormality
Overcurrent to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Motor RPM abnormality
Overcurrent to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Check & Remedy
Use SIM04-03 to check the operation of the suction
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT control PWB.
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT control PWB.
MX-7500N TROUBLESHOOTING 7 – 50
UE-11
LCT1 exhaust fan motor trouble
UE-12
LCT1 warm air heater thermistor open
UE-13
LCT1 warm air heater thermistor low
temperature trouble
temperature trouble
UE-14
LCT1 warm air heater thermistor high
temperature trouble
temperature trouble
UE-15
LCT1 warm air outlet port thermistor
open
open
UE-16
LCT1 warm air outlet port thermistor
low temperature
low temperature
UE-17
LCT1 warm air outlet port thermistor
high temperature
high temperature
UE-20
LCT2 suction fan motor trouble
Trouble content
Exhaust fan motor abnormality
Detail
PCU
Cause
Motor lock
Motor RPM abnormality
Over current to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Motor RPM abnormality
Over current to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Check & Remedy
Use SIM04-03 to check the operation of the exhaust
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT control PWB.
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT control PWB.
Trouble content
The thermistor is open.
Detail
PCU
Cause
Warm air heater (thermistor) trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
Check & Remedy
Check the harness and the connector from the warm
air heater (thermistor) to the A3 2-stage LCT control
PWB.
air heater (thermistor) to the A3 2-stage LCT control
PWB.
Trouble content
The temperature does not reach the specified level
within the specified time after turning ON the power
relay.
within the specified time after turning ON the power
relay.
Detail
PCU
Cause
Warm air heater (thermistor) trouble
Warm air heater trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Thermostat trouble.
AC power trouble
Insertion detection switch 2 trouble
Heater relay PWB trouble
Warm air heater trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Thermostat trouble.
AC power trouble
Insertion detection switch 2 trouble
Heater relay PWB trouble
Check & Remedy
Check the warm air heater (thermistor) and its
harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check for disconnection of the warm air heater and
the thermostat.
Check the insertion detection switch 2.
Check the heater relay PWB.
Check the heater control circuit of the AC PWB and
that of the A3 2-stage LCT control PWB.
harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check for disconnection of the warm air heater and
the thermostat.
Check the insertion detection switch 2.
Check the heater relay PWB.
Check the heater control circuit of the AC PWB and
that of the A3 2-stage LCT control PWB.
Trouble content
The warm air heater temperature exceeds the
specified level.
specified level.
Detail
PCU
Cause
Warm air heater (thermistor) trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
Heater relay PWB trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
Heater relay PWB trouble
Check & Remedy
Check the warm air heater (thermistor) and its
harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check the heater relay PWB.
Check the heater control circuit of the A3 2-stage LCT
control PWB.
harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check the heater relay PWB.
Check the heater control circuit of the A3 2-stage LCT
control PWB.
Trouble content
The thermistor is open.
Detail
PCU
Cause
Thermistor trouble.
A3 2-stage LCT control PWB trouble
Connector connection trouble
A3 2-stage LCT control PWB trouble
Connector connection trouble
Check & Remedy
Check connection of the harness and the connector
from the thermistor to the A3 2-stage LCT control
PWB.
from the thermistor to the A3 2-stage LCT control
PWB.
Trouble content
The temperature does not reach the specified level
within the specified time after turning ON the power
relay.
within the specified time after turning ON the power
relay.
Detail
PCU
Cause
Thermistor trouble.
Warm air heater trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Thermostat trouble.
AC power trouble
Insertion detection switch 2 trouble
Heater relay PWB trouble
Warm air heater trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Thermostat trouble.
AC power trouble
Insertion detection switch 2 trouble
Heater relay PWB trouble
Check & Remedy
Check the thermistor and its harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check for disconnection of the warm air heater and
the thermostat.
Check the insertion detection switch 2.
Check the heater relay PWB.
Check the heater control circuit of the AC PWB and
that of the A3 2-stage LCT control PWB.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check for disconnection of the warm air heater and
the thermostat.
Check the insertion detection switch 2.
Check the heater relay PWB.
Check the heater control circuit of the AC PWB and
that of the A3 2-stage LCT control PWB.
Trouble content
The temperature at the warm air outlet port exceeds
the specified level.
the specified level.
Detail
PCU
Cause
Thermistor trouble.
Warm air heater harness and connector connection
trouble
Heater relay PWB trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
Heater relay PWB trouble
A3 2-stage LCT control PWB trouble
Check & Remedy
Check the thermistor and its harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check the heater relay PWB.
Check the heater control circuit of the A3 2-stage LCT
control PWB.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check the heater relay PWB.
Check the heater control circuit of the A3 2-stage LCT
control PWB.
Trouble content
Suction fan motor abnormality
Detail
PCU
Cause
Motor lock
Motor RPM abnormality
Overcurrent to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Motor RPM abnormality
Overcurrent to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Check & Remedy
Use SIM04-03 to check the operation of the suction
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT controller PWB.
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT controller PWB.
MX-7500N TROUBLESHOOTING 7 – 51
UE-21
LCT2 exhaust fan motor trouble
UE-22
LCT2 warm air heater thermistor open
UE-23
LCT2 warm air heater thermistor low
temperature trouble
temperature trouble
UE-24
LCT2 warm air heater thermistor high
temperature trouble
temperature trouble
UE-25
LCT2 warm air outlet port thermistor
open
open
UE-26
LCT2 warm air outlet port thermistor
low temperature
low temperature
UE-27
LCT2 warm air outlet port thermistor
high temperature
high temperature
UE-30
LCT3 suction fan motor trouble
Trouble content
Exhaust fan motor abnormality
Detail
PCU
Cause
Motor lock
Motor RPM abnormality
Overcurrent to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Motor RPM abnormality
Overcurrent to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Check & Remedy
Use SIM04-03 to check the operation of the exhaust
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT control PWB.
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT control PWB.
Trouble content
The thermistor is open.
Detail
PCU
Cause
Warm air heater (thermistor) trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
Check & Remedy
Check the harness and the connector from the warm
air heater (thermistor) to the A3 2-stage LCT control
PWB.
air heater (thermistor) to the A3 2-stage LCT control
PWB.
Trouble content
The temperature does not reach the specified level
within the specified time after turning ON the power
relay.
within the specified time after turning ON the power
relay.
Detail
PCU
Cause
Warm air heater (thermistor) trouble
Warm air heater trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Thermostat trouble.
AC power trouble
Insertion detection switch 2 trouble
Heater relay PWB trouble
Warm air heater trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Thermostat trouble.
AC power trouble
Insertion detection switch 2 trouble
Heater relay PWB trouble
Check & Remedy
Check the warm air heater (thermistor) and its
harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check for disconnection of the warm air heater and
the thermostat.
Check the insertion detection switch 2.
Check the heater relay PWB.
Check the heater control circuit of the AC PWB and
that of the A3 2-stage LCT control PWB.
harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check for disconnection of the warm air heater and
the thermostat.
Check the insertion detection switch 2.
Check the heater relay PWB.
Check the heater control circuit of the AC PWB and
that of the A3 2-stage LCT control PWB.
Trouble content
The warm air heater temperature exceeds the
specified level.
specified level.
Detail
PCU
Cause
Warm air heater (thermistor) trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
Heater relay PWB trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
Heater relay PWB trouble
Check & Remedy
Check the warm air heater (thermistor) and its
harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check the heater relay PWB.
Check the heater control circuit of the A3 2-stage LCT
control PWB.
harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check the heater relay PWB.
Check the heater control circuit of the A3 2-stage LCT
control PWB.
Trouble content
The thermistor is open.
Detail
PCU
Cause
Thermistor trouble.
A3 2-stage LCT control PWB trouble
Connector connection trouble
A3 2-stage LCT control PWB trouble
Connector connection trouble
Check & Remedy
Check connection of the harness and the connector
from the thermistor to the A3 2-stage LCT control
PWB.
from the thermistor to the A3 2-stage LCT control
PWB.
Trouble content
The temperature does not reach the specified level
within the specified time after turning ON the power
relay.
within the specified time after turning ON the power
relay.
Detail
PCU
Cause
Thermistor trouble.
Warm air heater trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Thermostat trouble.
AC power trouble
Insertion detection switch 2 trouble
Heater relay PWB trouble
Warm air heater trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Thermostat trouble.
AC power trouble
Insertion detection switch 2 trouble
Heater relay PWB trouble
Check & Remedy
Check the thermistor and its harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check for disconnection of the warm air heater and
the thermostat.
Check the insertion detection switch 2.
Check the heater relay PWB.
Check the heater control circuit of the AC PWB and
that of the A3 2-stage LCT control PWB.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check for disconnection of the warm air heater and
the thermostat.
Check the insertion detection switch 2.
Check the heater relay PWB.
Check the heater control circuit of the AC PWB and
that of the A3 2-stage LCT control PWB.
Trouble content
The temperature at the warm air outlet port exceeds
the specified level.
the specified level.
Detail
PCU
Cause
Thermistor trouble.
Warm air heater harness and connector connection
trouble
Heater relay PWB trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
Heater relay PWB trouble
A3 2-stage LCT control PWB trouble
Check & Remedy
Check the thermistor and its harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check the heater relay PWB.
Check the heater control circuit of the A3 2-stage LCT
control PWB.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check the heater relay PWB.
Check the heater control circuit of the A3 2-stage LCT
control PWB.
Trouble content
Suction fan motor abnormality
Detail
PCU
Cause
Motor lock
Motor RPM abnormality
Over current to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Motor RPM abnormality
Over current to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Check & Remedy
Use SIM04-03 to check the operation of the suction
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT control PWB.
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT control PWB.
MX-7500N TROUBLESHOOTING 7 – 52
UE-31
LCT3 exhaust fan motor trouble
UE-32
LCT3 warm air heater thermistor open
UE-33
LCT3 warm air heater thermistor low
temperature trouble
temperature trouble
UE-34
LCT3 warm air heater thermistor high
temperature trouble
temperature trouble
UE-35
LCT3 warm air outlet port thermistor
open
open
UE-36
LCT3 warm air outlet port thermistor
low temperature
low temperature
UE-37
LCT3 warm air outlet port thermistor
high temperature
high temperature
UE-40
LCT4 suction fan motor trouble
Trouble content
Exhaust fan motor abnormality
Detail
PCU
Cause
Motor lock
Motor RPM abnormality
Over current to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Motor RPM abnormality
Over current to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Check & Remedy
Use SIM04-03 to check the operation of the exhaust
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT control PWB.
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT control PWB.
Trouble content
The thermistor is open.
Detail
PCU
Cause
Warm air heater (thermistor) trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
Check & Remedy
Check the harness and the connector from the warm
air heater (thermistor) to the A3 2-stage LCT control
PWB.
air heater (thermistor) to the A3 2-stage LCT control
PWB.
Trouble content
The temperature does not reach the specified level
within the specified time after turning ON the power
relay.
within the specified time after turning ON the power
relay.
Detail
PCU
Cause
Warm air heater (thermistor) trouble
Warm air heater trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Thermostat trouble.
AC power trouble
Insertion detection switch 2 trouble
Heater relay PWB trouble
Warm air heater trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Thermostat trouble.
AC power trouble
Insertion detection switch 2 trouble
Heater relay PWB trouble
Check & Remedy
Check the warm air heater (thermistor) and its har-
ness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check for disconnection of the warm air heater and
the thermostat.
Check the insertion detection switch 2.
Check the heater relay PWB.
Check the heater control circuit of the AC PWB and
that of the A3 2-stage LCT control PWB.
ness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check for disconnection of the warm air heater and
the thermostat.
Check the insertion detection switch 2.
Check the heater relay PWB.
Check the heater control circuit of the AC PWB and
that of the A3 2-stage LCT control PWB.
Trouble content
The warm air heater temperature exceeds the
specified level.
specified level.
Detail
PCU
Cause
Warm air heater (thermistor) trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
Heater relay PWB trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
Heater relay PWB trouble
Check & Remedy
Check the warm air heater (thermistor) and its har-
ness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check the heater relay PWB.
Check the heater control circuit of the A3 2-stage LCT
control PWB.
ness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check the heater relay PWB.
Check the heater control circuit of the A3 2-stage LCT
control PWB.
Trouble content
The thermistor is open.
Detail
PCU
Cause
Thermistor trouble.
A3 2-stage LCT control PWB trouble
Connector connection trouble
A3 2-stage LCT control PWB trouble
Connector connection trouble
Check & Remedy
Check connection of the harness and the connector
from the thermistor to the A3 2-stage LCT control
PWB.
from the thermistor to the A3 2-stage LCT control
PWB.
Trouble content
The temperature does not reach the specified level
within the specified time after turning ON the power
relay.
within the specified time after turning ON the power
relay.
Detail
PCU
Cause
Thermistor trouble.
Warm air heater trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Thermostat trouble.
AC power trouble
Insertion detection switch 2 trouble
Heater relay PWB trouble
Warm air heater trouble
Warm air heater harness and connector connection
trouble
A3 2-stage LCT control PWB trouble
Thermostat trouble.
AC power trouble
Insertion detection switch 2 trouble
Heater relay PWB trouble
Check & Remedy
Check the thermistor and its harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check for disconnection of the warm air heater and
the thermostat.
Check the insertion detection switch 2.
Check the heater relay PWB.
Check the heater control circuit of the AC PWB and
that of the A3 2-stage LCT control PWB.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check for disconnection of the warm air heater and
the thermostat.
Check the insertion detection switch 2.
Check the heater relay PWB.
Check the heater control circuit of the AC PWB and
that of the A3 2-stage LCT control PWB.
Trouble content
The temperature at the warm air outlet port exceeds
the specified level.
the specified level.
Detail
PCU
Cause
Thermistor trouble.
Warm air heater harness and connector connection
trouble
Heater relay PWB trouble
A3 2-stage LCT control PWB trouble
Warm air heater harness and connector connection
trouble
Heater relay PWB trouble
A3 2-stage LCT control PWB trouble
Check & Remedy
Check the thermistor and its harness.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check the heater relay PWB.
Check the heater control circuit of the A3 2-stage LCT
control PWB.
Check the thermistor input circuit section of the A3 2-
stage LCT control PWB.
Check the heater relay PWB.
Check the heater control circuit of the A3 2-stage LCT
control PWB.
Trouble content
Suction fan motor abnormality
Detail
PCU
Cause
Motor lock
Motor RPM abnormality
Over current to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Motor RPM abnormality
Over current to the motor
Harness and connector connection trouble
A3 2-stage LCT control PWB trouble
Check & Remedy
Use SIM04-03 to check the operation of the suction
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT controller PWB.
fan motor.
Check connection of the harness and the connector.
Replace the A3 2-stage LCT controller PWB.
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