2006 INFINITI M35 check

TROUBLE DIAGNOSIS
ATC-93
C
D
E
F
G
H
I
K
L
MA
B
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

ATC-94
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
Magnet Clutch CircuitNJS000GU
SYMPTOM: Magnet clutch does not engage.
INSPECTION FLOW
*1ATC-122, "Intake Sensor Circuit"*2ATC-113, "Ambient Sensor Circuit"*3AT C - 5 6 , "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13.
*4ATC-95, "
DIAGNOSIS PROCE-
DURE FOR MAGNET CLUTCH"
*5ATC-105, "TROUBLE DIAGNOSIS
FOR UNUSUAL PRESSURE"
*6AT C - 6 4 , "Operational Check"
*7ATC-56, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 2 to 6.*8ATC-41, "
SYMPTOM TABLE"
RJIA4077E

ATC-96
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
1. CHECK AMBIENT SENSOR AND INTAKE SENSOR CIRCUIT
Check ambient sensor and intake sensor. Refer to AT C - 5 6 , "
FUNCTION CONFIRMATION PROCEDURE" ,
see No. 9 and 11.
OK or NG
OK >> GO TO 2.
NG >>
Malfunctioning ambient sensor: Refer to AT C - 11 3 , "Ambient Sensor Circuit" .
Malfunctioning intake sensor: Refer to ATC-122, "Intake Sensor Circuit" .
2. PERFORM AUTO ACTIVE TEST
Refer to PG-24, "
Auto Active Test" .
Does the magnet clutch operate?
YES >>WITH CONSULT-II: GO TO 5.
WITHOUT CONSULT-II: GO TO 6.
NO >> Check 10A fuse (No. 79, located in IPDM E/R), and GO TO 3.
3. CHECK CIRCUIT CONTINUITY BETWEEN IPDM E/R AND COMPRESSOR
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R connector and compressor connector.
3. Check continuity between IPDM E/R harness connector E8 ter-
minal 34 and compressor harness connector F24 terminal 1.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4. CHECK MAGNET CLUTCH CIRCUIT
Check for operation sound when applying battery voltage direct cur-
rent to terminal.
OK or NG
OK >> 1. Replace IPDM E/R.
2. Go to self-diagnosis procedure AT C - 5 6 , "
FUNCTION
CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-4. Confirm that magnet clutch opera-
tion normal.
NG >> 1. Replace compressor.
2. Go to self-diagnosis procedure AT C - 5 6 , "
FUNCTION
CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-4. Confirm that magnet clutch operation normal.
34 – 1 : Continuity should exist.
RJIA4079E
RJIA2005E

TROUBLE DIAGNOSIS
ATC-97
C
D
E
F
G
H
I
K
L
MA
B
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

ATC-98
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
8. CHECK CAN COMMUNICATION
Check CAN communication. Refer to EC-173, "
DTC U1000, U1001 CAN COMMUNICATION LINE"
(VQ35DE) or EC-886, "DTC U1000, U1001 CAN COMMUNICATION LINE" (VK45DE).
ECM – IPDM E/R
ECM – Unified meter and A/C amp.
OK or NG
OK >> Replace ECM.
NG >> Repair or replace malfunctioning part(s).
COMPONENT INSPECTION
Refrigerant Pressure Sensor
The refrigerant pressure sensor is attached to the liquid tank.
Make sure that the A/C refrigerant pressure and the sensor output
voltage are within the specified range as shown in the A/C operating
condition figure. Refer to EC-692, "
REFRIGERANT PRESSURE
SENSOR" (VQ35DE) or EC-1434, "REFRIGERANT PRESSURE
SENSOR" (VK45DE).
RJIA4080E
RJIA2954E

ATC-100
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
*1ATC-56, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 2 to 6.*2ATC-83, "
Air Mix Door Motor Circuit"*3ATC-103, "Test Reading
(VQ35DE)" or ATC-104, "Test
Reading (VK45DE)"
*4ATC-62, "AUXILIARY MECHA-
NISM: TEMPERATURE SETTING
TRIMMER"
*5ATC-56, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13.*6ATC-70, "
LAN System Circuit"
*7ATC-89, "Blower Motor Circuit"*8ATC-94, "Magnet Clutch Circuit"*9ATC-101, "PERFORMANCE TEST
DIAGNOSIS"
*10ATC-64, "Operational Check"*11AT C - 7 , "CONTAMINATED REFRIG-
ERANT"
*12EM-15, "Checking Drive Belts"
(VQ35DE) or EM-174, "
Checking
Drive Belts" (VK45DE)
*13EC-512, "
SYSTEM DESCRIPTION"
(VQ35DE) or EC-1239, "
SYSTEM
DESCRIPTION" (VK45DE)

ATC-102
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
*1ATC-157, "Check Disc to Pulley
Clearance"
*2ATC-89, "Blower Motor Circuit"*3EM-15, "Checking Drive Belts"
(VQ35DE) or EM-174, "
Checking
Drive Belts" (VK45DE)
SJIA1642E

TROUBLE DIAGNOSIS
ATC-105
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2006 January2006 M35/M45
TROUBLE DIAGNOSIS FOR UNUSUAL PRESSURE
Whenever system’s high and/or low side pressure(s) is/are unusual, diagnose using a manifold gauge. The
marker above the gauge scale in the following tables indicates the standard (usual) pressure range. Since the
standard (usual) pressure, however, differs from vehicle to vehicle, refer to above table (Ambient air tempera-
ture-to-operating pressure table).
Both High- and Low-pressure Sides are Too High
High-pressure Side is Too High and Low-pressure Side is Too Low
Gauge indication Refrigerant cycle Probable cause Corrective action
Both high- and low-pressure sides
are too high.The pressure returns to nor-
mal soon after water is
splashed on condenser.Excessive refrigerant charge
in refrigeration cycle.Reduce refrigerant until speci-
fied pressure is obtained.
Air suction by cooling fan is
insufficient.Insufficient condenser cooling
performance.
1. Condenser fins are clogged.
2. Improper fan rotation of
cooling fan.
Clean condenser.
Check and repair cooling fan
as necessary.
Low-pressure pipe is not
cold.
When compressor is
stopped high-pressure
value quickly drops by
approximately 196 kPa (2
kg/cm
2 , 28 psi). It then
decreases gradually there-
after.Poor heat exchange in con-
denser
(After compressor operation
stops, high-pressure
decreases too slowly.).Air in refrigeration cycle.Evacuate repeatedly and
recharge system.
Engine tends to overheat.Engine cooling systems mal-
function.Check and repair each engine
cooling system.
An area of the low-pres-
sure pipe is colder than
areas near the evaporator
outlet.
Low-pressure pipe is
sometimes covered with
frost.
Excessive liquid refrigerant
on low-pressure side.
Excessive refrigerant dis-
charge flow.
Expansion valve is open a
little compared with the
specification.

Improper expansion valve
adjustment.Replace expansion valve.
AC359A
Gauge indication Refrigerant cycle Probable cause Corrective action
High-pressure side is too high and
low-pressure side is too low.
Upper side of condenser and
high-pressure side are hot,
however, liquid tank is not so
hot.High-pressure tube or parts
located between compressor
and condenser are clogged or
crushed.
Check and repair or replace
malfunctioning parts.
Check lubricant for contami-
nation.
AC360A