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TROUBLE DIAGNOSIS
ATC-91
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Revision: 2007 April2007 M35/M45
1. CHECK POWER SUPPLY FOR BLOWER MOTOR
1. Disconnect blower motor connector.
2. Turn ignition switch ON.
3. Check voltage between blower motor harness connector M91
terminal 1 and ground.
OK or NG
OK >> GO TO 2.
NG >> Check power supply circuit and 15A fuses [Nos. 10 and
11, located in the fuse block (J/B)]. Refer to PG-114,
"FUSE BLOCK - JUNCTION BOX (J/B)" .
If fuses are OK, check harness for open circuit. Repair or replace if necessary.
If fuses are NG, check harness for short circuit and replace fuse.
2. CHECK BLOWER MOTOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between blower motor harness connector M91
terminal 3 and ground.
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
3. CHECK CIRCUIT CONTINUITY BETWEEN BLOWER MOTOR AND UNIFIED METER AND A/C AMP.
1. Disconnect unified meter and A/C amp. connector.
2. Check continuity between blower motor harness connector M91
terminal 2 and unified meter and A/C amp. harness connector
M64 terminal 38.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.1 – Ground : Battery voltage
RJIA1997E
3 – Ground : Continuity should exist.
RJIA4072E
2 – 38 : Continuity should exist.
RJIA4073E
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ATC-92
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
4. CHECK UNIFIED METER AND A/C AMP. OUTPUT SIGNAL
1. Reconnect blower motor connector and unified meter and A/C
amp. connector.
2. Turn ignition switch ON.
3. Set MODE switch to VENT position.
4. Change the fan speed from Lo to Hi, and check the duty ratios
between blower motor harness connector M91 terminal 2 and
ground by using an oscilloscope. Normal terminal 2 drive signal
duty ratios are shown in the table below.
OK or NG
OK >> Replace blower motor after confirming the fan air flow does not change.
NG >> Replace unified meter and A/C amp.
COMPONENT INSPECTION
Blower Motor
Confirm smooth rotation of the blower motor.
Ensure that there are no foreign particles inside the blower unit.
RJIA4074E
RJIA4075E
RJIA4076E
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ATC-96
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
5. CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
Check compressor ON/OFF signal. Refer to AT C - 4 0 , "
CONSULT-II
Function (ECM)" .
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
6. CHECK REFRIGERANT PRESSURE SENSOR
WITH CONSULT-II
1. Start the engine.
2. Check voltage of refrigerant pressure sensor. Refer to EC-138, "
CONSULT-II Reference Value in Data
Monitor" (VQ35DE) or EC-841, "CONSULT-II Reference Value in Data Monitor" (VK45DE).
WITHOUT CONSULT-II
1. Start the engine.
2. Check voltage between ECM harness connector F108 terminal
70 and ground.
OK or NG
OK >>WITH CONSULT-II: GO TO 7.
WITHOUT CONSULT-II: Repair harness or connector.
NG >> Refer to EC-704, "
REFRIGERANT PRESSURE SENSOR" (VQ35DE) or EC-1424, "REFRIGER-
ANT PRESSURE SENSOR" (VK45DE).
7. CHECK ECM INPUT (FAN ON) SIGNAL
Check FAN ON/OFF signal. Refer to AT C - 4 0 , "
CONSULT-II Function
(ECM)" .
OK or NG
OK >> GO TO 8.
NG >> Repair harness or connector.A/C SW ON : AIR COND SIG ON
A/C SW OFF : AIR COND SIG OFF
RJIA3646E
Terminals
Condition Voltage (+)
(−)
ECM
connectorTerminal
No.
F108 70 GroundA/C switch: ON
(Blower motor operates.)Approx. 1.0 -
4.0 V
PBIB1188E
FAN SW ON : HEATER FAN SW ON
FAN SW OFF : HEATER FAN SW OFF
RJIA3646E
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TROUBLE DIAGNOSIS
ATC-99
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Revision: 2007 April2007 M35/M45
*1ATC-57, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 2 to 6.*2ATC-82, "
Air Mix Door Motor Circuit"*3ATC-102, "Test Reading
(VQ35DE)" or ATC-103, "Test
Reading (VK45DE)"
*4ATC-63, "AUXILIARY MECHA-
NISM: TEMPERATURE SETTING
TRIMMER"
*5ATC-57, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13.*6ATC-71, "
LAN System Circuit"
*7ATC-88, "Blower Motor Circuit"*8ATC-93, "Magnet Clutch Circuit"*9ATC-100, "PERFORMANCE TEST
DIAGNOSIS"
*10ATC-65, "Operational Check"*11AT C - 7 , "CONTAMINATED REFRIG-
ERANT"
*12EM-16, "Checking Drive Belts"
(VQ35DE) or EM-174, "
Checking
Drive Belts" (VK45DE)
*13EC-499, "
SYSTEM DESCRIPTION"
(VQ35DE) or EC-1214, "
SYSTEM
DESCRIPTION" (VK45DE)
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TROUBLE DIAGNOSIS
ATC-101
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Revision: 2007 April2007 M35/M45
*1ATC-156, "Check Disc to Pulley
Clearance"
*2ATC-88, "Blower Motor Circuit"*3EM-16, "Checking Drive Belts"
(VQ35DE) or EM-174, "
Checking
Drive Belts" (VK45DE)
SJIA1642E
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TROUBLE DIAGNOSIS
ATC-105
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Revision: 2007 April2007 M35/M45
High-pressure Side is Too Low and Low-pressure Side is Too High
Both High- and Low-pressure Sides are Too Low
Gauge indication Refrigerant cycle Probable cause Corrective action
High-pressure side is too low and
low-pressure side is too high.High- and low-pressure sides
become equal soon after com-
pressor operation stops.Compressor pressure opera-
tion is improper.
↓
Damaged inside compressor
packings.Replace compressor.
No temperature difference
between high- and low-pres-
sure sides.Compressor pressure opera-
tion is improper.
↓
Damaged inside compressor
packings.Replace compressor.
AC356A
Gauge indication Refrigerant cycle Probable cause Corrective action
Both high- and low-pressure sides
are too low.
There is a big temperature
difference between liquid
tank outlet and inlet. Outlet
temperature is extremely
low.
Liquid tank inlet and expan-
sion valve are frosted.Liquid tank inside is slightly
clogged.
Replace liquid tank.
Check lubricant for contami-
nation.
Temperature of expansion
valve inlet is extremely low
as compared with areas
near liquid tank.
Expansion valve inlet is
frosted.
Temperature difference
occurs somewhere in high-
pressure side.High-pressure pipe located
between liquid tank and
expansion valve is clogged.
Check and repair malfunc-
tioning parts.
Check lubricant for contami-
nation.
Expansion valve and liquid
tank are warm or slightly cool
when touched.Low refrigerant charge.
↓
Leaking fittings or compo-
nents.Check refrigerant for leaks.
Refer to ATC-169, "
Checking
for Refrigerant Leaks" .
There is a big temperature dif-
ference between expansion
valve inlet and outlet while the
valve itself is frosted.Expansion valve closes a little
compared with the specifica-
tion.
↓
1. Improper expansion valve
adjustment.
2. Malfunctioning expansion
valve.
3. Outlet and inlet may be
clogged.
Remove foreign particles by
using compressed air.
Replace expansion valve.
Check lubricant for contami-
nation.
An area of the low-pressure
pipe is colder than areas near
the evaporator outlet.Low-pressure pipe is clogged
or crushed.
Check and repair malfunc-
tioning parts.
Check lubricant for contami-
nation.
Air flow volume is not enough
or is too low.Evaporator is frozen.
Check intake sensor circuit.
Refer to ATC-121, "
Intake
Sensor Circuit" .
Replace compressor.
Repair evaporator fins.
Replace evaporator.
Refer to AT C - 8 8 , "Blower
Motor Circuit" .
AC353A
Page 559 of 4647
ATC-108
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
Insufficient HeatingNJS000GW
SYMPTOM: Insufficient heating
INSPECTION FLOW
*1ATC-65, "Operational Check"*2AT C - 8 2 , "Air Mix Door Motor Circuit"*3ATC-57, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 2 to
6.
*4ATC-57, "
FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13.*5AT C - 7 1 , "
LAN System Circuit"*6ATC-88, "Blower Motor Circuit"
*7EC-214, "DTC P0117, P0118 ECT
SENSOR" (VQ35DE) or EC-926,
"DTC P0117, P0118 ECT SEN-
SOR" (VK45DE)*8CO-11, "
Changing Engine Coolant"
(VQ35DE) or CO-40, "
Changing
Engine Coolant" (VK45DE)*9CO-16, "
Checking Radiator Cap"
(VQ35DE) or CO-45, "
Checking
Radiator Cap" (VK45DE)
RJIA4084E
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BLOWER UNIT
ATC-129
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Revision: 2007 April2007 M35/M45
BLOWER UNITPFP:27200
Removal and InstallationNJS000IA
REMOVAL
1. Remove instrument passenger lower cover and glove box cover. Refer to IP-10, "INSTRUMENT PANEL
ASSEMBLY" .
2. Remove BCM. Refer to BCS-15, "
Removal and Installation of BCM" .
3. Remove mounting nuts, and then remove ECM with bracket
attached.
4. Disconnect intake door motor connector and blower fan motor
connector.
5. Remove mounting bolt and screw from blower unit.
CAUTION:
Move blower unit rightward, and remove locating pin (1
part) and joint. Then remove blower unit downward.
6. Remove blower unit.
INSTALLATION
Installation is basically the reverse order of removal.
CAUTION:
Make sure locating pin (1 part) and joint are securely inserted.
R J I A 4 111 E
RJIA4112E