2006 INFINITI M35 ground

ATC-68
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
1. CHECK POWER SUPPLY CIRCUIT FOR UNIFIED METER AND A/C AMP.
1. Disconnect unified meter and A/C amp. connector.
2. Check voltage between unified meter and A/C amp. harness
connector M65 terminals 41, 53 and 55 and ground.
OK or NG
OK >> GO TO 2.
NG >> Check 10A fuses [Nos. 6, 12 and 19, located in the fuse block (J/B)]. Refer to P G - 111 , "
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 GROUND CIRCUIT FOR UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Check continuity between unified meter and A/C amp. harness
connector M65 terminal 55, 71 and ground.
OK or NG
OK >> Replace unified meter and A/C amp.
NG >> Repair harness or connector.
Terminals Ignition switch position
(+)
(-) OFF ACC ON Unified
meter and
A/C amp.
connectorTerminal
No.
M65 41
GroundApprox. 0 VBattery
voltageBattery
voltage
M65 53 Approx. 0 V Approx. 0 VBattery
voltage
M65 54Battery
voltageBattery
voltageBattery
voltage
RJIA4050E
55, 71 – Ground : Continuity should exist.
RJIA4051E

TROUBLE DIAGNOSIS
ATC-69
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AT C
Revision: 2006 January2006 M35/M45
Rear Control Switch CircuitNJS000GM
DIAGNOSIS PROCEDURE FOR REAR CONTROL SWITCH
SYMPTOM: Rear control switch does not operate.
1. CHECK A/C SYSTEM
Check multifunction switch, confirm A/C system operation.
OK or NG
OK >> GO TO 2.
NG >> Go to trouble diagnosis procedure for A/C system. Refer to AT C - 6 6 , "
Power Supply and Ground
Circuit for Auto Amp." .
2. CHECK REAR CONTROL SWITCH
Check rear control switch, except for A/C switch (audio) operation.
OK or NG
OK >> GO TO 5.
NG >> GO TO 3.
3. CHECK POWER SUPPLY FOR REAR CONTROL SWITCH
1. Turn ignition switch OFF.
2. Disconnect rear control switch connector.
3. Turn ignition switch ACC.
4. Check voltage between rear control switch harness connector
B554 terminal 1 and ground.
OK or NG
OK >> GO TO 4.
NG >> Check 10A fuse [No. 6 located in the fuse block (J/B)].
Refer to P G - 111 , "
FUSE BLOCK - JUNCTION BOX (J/
B)" .
If fuse is OK, check harness for open circuit. Repair or replace if necessary.
If fuse is NG, check harness for short circuit and replace fuse.
4. CHECK GROUND CIRCUIT FOR REAR CONTROL SWITCH
1. Turn ignition switch OFF.
2. Check continuity between rear control switch harness connector
B554 terminal 4 and ground.
OK or NG
OK >> GO TO 5.
NG >> Repair harness or connector.
5. CHECK REAR CONTROL SWITCH, AV CONTROL UNIT OR NAVI CONTROL UNIT
Check circuit between rear control switch and AV control unit or NAVI control unit AV- 1 0 8 , "
TROUBLE DIAG-
NOSIS" (Without mobile entertainment system) or AV- 2 5 3 , "TROUBLE DIAGNOSIS" (With mobile entertain-
ment system).
OK or NG
OK >> Replace rear control switch.
NG >> Replace part or repair for result trouble diagnosis.1 – Ground : Battery voltage
RJIA3996E
4 – Ground : Continuity should exist.
RJIA3997E

ATC-70
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
LAN System CircuitNJS000GN
SYMPTOM: Mode door motors, upper ventilator door motor, air mix door motors and intake door motor does
not operate normally.
DIAGNOSIS PROCEDURE FOR LAN CIRCUIT
1. CHECK POWER SUPPLY FOR UNIFIED METER AND A/C AMP.
1. Turn ignition switch ON.
2. Check voltage between unified meter and A/C amp. harness
connector M65 terminal 70 and ground.
OK or NG
OK >> GO TO 2.
NG >> Replace unified meter and A/C amp.
2. CHECK SIGNAL FOR UNIFIED METER AND A/C AMP.
Confirm A/C LAN signal between unified meter and A/C amp. har-
ness connector M65 terminal 69 and ground using an oscilloscope.
OK or NG
OK >> GO TO 3.
NG >> Replace unified meter and A/C amp.
RJIA4052E
70 – Ground : Battery voltage
RJIA4053E
Terminals
Voltage (+)
(
)
Unified meter and
A/C amp. connectorTe r m i n a l N o .
M65 69 Ground
RJIA4054E
SJIA1453J

TROUBLE DIAGNOSIS
ATC-71
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AT C
Revision: 2006 January2006 M35/M45
3. CHECK POWER SUPPLY FOR EACH DOOR MOTOR
Check voltage between each door motor harness connector terminal
1 and ground.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4. CHECK SIGNAL FOR EACH DOOR MOTOR
Confirm A/C LAN signal between each door motor harness connec-
tor terminal 3 and ground using an oscilloscope.
OK or NG
OK >> GO TO 5.
NG >> Repair harness or connector.
5. CHECK MOTOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect each door motor connector.
3. Check continuity between each door motor harness connector
terminal 2 and ground.
OK or NG
OK >> GO TO 6.
NG >> Repair harness or connector.1 – Ground : Battery voltage
RJIA1988E
Door motorTerminals
Voltag e (+)
()
Con-
nectorTerminal
No.
Mode (Driver
side)M252 3
Ground Mode (Pas-
senger side)M255 3
Upper venti-
latorM254 3
Air mix
(Driver side)M253 3
Air mix (Pas-
senger side)M256 3
Intake M257 3
RJIA1989E
SJIA1453J
2 – Ground : Continuity should exist.
RJIA1990E

ATC-92
TROUBLE DIAGNOSIS
Revision: 2006 January2006 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 P G - 111 ,
"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

TROUBLE DIAGNOSIS
ATC-93
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AT C
Revision: 2006 January2006 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. 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

TROUBLE DIAGNOSIS
ATC-97
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AT C
Revision: 2006 January2006 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-149, "
CONSULT-II Reference Value in Data
Monitor" (VQ35DE) or EC-862, "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-692, "
REFRIGERANT PRESSURE SENSOR" (VQ35DE) or EC-1434, "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

TROUBLE DIAGNOSIS
ATC-107
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AT C
Revision: 2006 January2006 M35/M45
Low-pressure Side Sometimes Becomes Negative
Low-pressure Side Becomes Negative
DIAGNOSIS PROCEDURE FOR INSUFFICIENT COOLING
SYMPTOM: Insufficient cooling
1. CHECK POWER SUPPLY FOR ECV (ELECTRONIC CONTROL VALVE)
1. Disconnect compressor (ECV) connector.
2. Turn ignition switch ON.
3. Check voltage between compressor (ECV) harness connector
F34 terminal 2 and ground.
OK or NG
OK >> GO TO 2.
NG >> Check power supply circuit and 10A fuse [No. 12,
located in the fuse block (J/B)]. Refer to P G - 111 , "
FUSE
BLOCK - JUNCTION BOX (J/B)" .
If fuse is OK, check harness for open circuit. Repair or replace if necessary.
If fuse is NG, check harness for short circuit and replace fuse.
Gauge indication Refrigerant cycle Probable cause Corrective action
Low-pressure side sometimes
becomes negative.
Air conditioning system
does not function and does
not cyclically cool the com-
partment air.
The system constantly func-
tions for a certain period of
time after compressor is
stopped and restarted.Refrigerant does not dis-
charge cyclically.
Moisture is frozen at expan-
sion valve outlet and inlet.
Water is mixed with refriger-
ant.
Drain water from refrigerant
or replace refrigerant.
Replace liquid tank.
AC354A
Gauge indication Refrigerant cycle Probable cause Corrective action
Low-pressure side becomes nega-
tive.
Liquid tank or front/rear side of
expansion valve’s pipe is
frosted or wet with dew.High-pressure side is closed
and refrigerant does not flow.
Expansion valve or liquid tank
is frosted.Leave the system at rest until
no frost is present. Start it
again to check whether or not
the malfunction is caused by
water or foreign particles.
If water is the cause, initially
cooling is okay. Then the
water freezes causing a
blockage. Drain water from
refrigerant or replace refrig-
erant.
If due to foreign particles,
remove expansion valve
and remove the particles
with dry and compressed air
(not shop air).
If either of the above meth-
ods cannot correct the mal-
function, replace expansion
valve.
Replace liquid tank.
Check lubricant for contami-
nation.
AC362A
2 – ground : Battery voltage
RJIA4213E