air condition INFINITI M35 2007 Factory Service Manual

AIR CONDITIONER CONTROL
ATC-37
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AT C
Revision: 2007 April2007 M35/M45
Discharge Air FlowNJS000GA
RJIA4024E

ATC-38
AIR CONDITIONER CONTROL
Revision: 2007 April2007 M35/M45
System DescriptionNJS000GB
SWITCHES AND THEIR CONTROL FUNCTION
SJIA1730E
SJIA1766E

AIR CONDITIONER CONTROL
ATC-39
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Revision: 2007 April2007 M35/M45
CAN Communication System DescriptionNJS000GC
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only. For details, refer to LAN-50,
"CAN System Specification Chart" .

ATC-40
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
TROUBLE DIAGNOSISPFP:00004
CONSULT-II Function (ECM)NJS000GD
CONSULT-II can display each diagnosis item using the diagnosis test modes shown following.
CONSULT-II BASIC OPERATION
Refer to GI-38, "CONSULT-II Start Procedure" .
DATA MONITOR
Operation Procedure
1. Touch “ENGINE” on “SELECT SYSTEM” screen.
2. Touch “DATA MONITOR” on “SELECT DIAG MODE” screen.
3. Touch “SELECTION FROM MENU” on “DATA MONITOR” screen.
4. When “SELECTION FROM MENU” is selected, touch items to be monitored.
5. Touch “START”.
6. Touch “RECORD” while monitoring, then the status of the monitored item can be recorded. To stop
recording, touch “STOP”.
Display Item List
How to Perform Trouble Diagnosis for Quick and Accurate RepairNJS000GE
WORK FLOW
System part Check item, diagnosis mode Description
ECM Data monitor Displays ECM input data in real time.
Monitor item name
“operation or unit”Contents
AIR COND SIG “ON/OFF” Displays “COMP (ON)/COMP (OFF)” status as judged from air conditioner switch signal.
HEATER FAN SW “ON/OFF” Displays “FAN (ON)/FAN (OFF)” status as judged from blower fan motor switch signal.
IGNITION SW “ON/OFF” Displays “IGN position (ON)/OFF, ACC position (OFF)” status as judged from ignition switch signal.
AC PRESS SEN “V”Displays “Refrigerant pressure sensor for voltage” status as inputted from refrigerant pressure sen-
sor.
*1ATC-65, "Operational Check"
SHA900E

TROUBLE DIAGNOSIS
ATC-65
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AT C
Revision: 2007 April2007 M35/M45
Operational CheckNJS000GK
The purpose of the operational check is to check if the individual system operates properly.
CHECKING MEMORY FUNCTION
1. Press the temperature control (UP) switch (driver side) until 32°C (90°F) is displayed.
2. Press OFF switch.
3. Turn ignition switch OFF.
4. Turn ignition switch ON.
5. Press the AUTO switch.
6. Confirm that the set temperature remains at previous temperature.
7. Press OFF switch.
If NG, go to trouble diagnosis procedure for AT C - 111 , "
Memory Function" .
If OK, continue the check.
CHECKING BLOWER
1. Press fan (UP:+) switch. Blower should operate on low speed. The fan symbol should have one blade lit.
2. Press fan (UP:+) switch again, and continue checking blower speed and fan symbol until all speeds are
checked.
3. Leave blower on max. speed.
If NG, go to trouble diagnosis procedure for AT C - 8 8 , "
Blower Motor Circuit" .
If OK, continue the check.
CHECKING DISCHARGE AIR (MODE SWITCH AND DEF SWITCH)
1. Press MODE switch and DEF switch.
2. Each position indicator should change shape.
3. Confirm that discharge air comes out according to the air distribution table. Refer to AT C - 3 7 , "
Discharge
Air Flow" .
If NG, go to trouble diagnosis procedure for AT C - 7 6 , "
Mode Door Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual inspection) and intake door position is at
FRESH when the D/F or DEF is selected.Conditions : Engine running at normal operating temperature
RJIA4035E

ATC-66
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
CHECKING DISCHARGE AIR (UPPER VENT SWITCH)
1. Press temperature control (UP) switch (driver side) until 32°C (90°F) is displayed.
2. Press fan (UP:+) switch until Max. speed.
3. Set MODE switch (driver side) to VENT position.
4. Press UPPER VENT switch. AUTO indicator should illuminate.
5. Press temperature control (DOWN) switch (driver side) until 18°C (60°F) is displayed.
6. Confirm that discharger air come out.
7. Press UPPER VENT switch again. AUTO indicator should OFF.
If NG, go to trouble diagnosis procedure for AT C - 7 9 , "
Upper Ventilator Door Motor Circuit" .
If OK, continue the check.
CHECKING INTAKE AIR
1. Press intake switch. Recirculation indicator should illuminate.
2. Press intake switch again. Fresh indicator should illuminate.
3. Listen for intake door position change. (Slight change of blower sound can be heard.)
If NG, go to trouble diagnosis procedure for AT C - 8 5 , "
Intake Door Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual inspection) and intake door position is at
FRESH when the D/F or DEF is selected.
CHECKING TEMPERATURE DECREASE
1. Press temperature control (DOWN) switch (driver side) until 18°C (60°F) is displayed.
2. Check for cold air at discharge air outlets.
If NG, go to trouble diagnosis procedure for AT C - 9 8 , "
Insufficient Cooling" .
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Press temperature control (UP) switch (driver side) until 32°C (90°F) is displayed.
2. Check for hot air at discharge air outlets.
If NG, go to trouble diagnosis procedure for ATC-108, "
Insufficient Heating" .
If OK, continue the check.
CHECKING A/C SWITCH
1. Press AUTO switch and A/C switch.
2. A/C switch indicator will turn ON.

Confirm that the compressor clutch engages (sound or visual inspection).
If NG, go to trouble diagnosis procedure for AT C - 9 3 , "
Magnet Clutch Circuit" .
If OK, continue the check.
CHECKING AUTO MODE
1. Press AUTO switch and A/C switch.
2. Display should indicate AUTO.

Confirm that discharge air and blower speed will depend on ambient, in-vehicle, and set temperatures.
If NG, go to trouble diagnosis procedure for AT C - 6 7 , "
Power Supply and Ground Circuit for Auto Amp." , then
if necessary, trouble diagnosis procedure for AT C - 9 3 , "
Magnet Clutch Circuit" .
If all operational checks are OK (symptom cannot be duplicated), go to Incident Simulation Tests in GI-28,
"How to Perform Efficient Diagnosis for an Electrical Incident" and perform tests as outlined to simulate driv-
ing conditions environment. If symptom appears, refer to AT C - 4 1 , "
SYMPTOM TABLE" and perform applica-
ble trouble diagnosis procedures.

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

TROUBLE DIAGNOSIS
ATC-97
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Revision: 2007 April2007 M35/M45
8. CHECK CAN COMMUNICATION
Check CAN communication. Refer to EC-161, "
DTC U1000, U1001 CAN COMMUNICATION LINE"
(VQ35DE) or EC-865, "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-704, "
REFRIGERANT PRESSURE
SENSOR" (VQ35DE) or EC-1424, "REFRIGERANT PRESSURE
SENSOR" (VK45DE).
RJIA4080E
RJIA2954E

ATC-102
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
PERFORMANCE CHART
Test Condition
Testing must be performed as follows:
Test Reading (VQ35DE)
Recirculating-to-discharge Air Temperature Table
Ambient Air Temperature-to-operating Pressure Table
Vehicle condition Indoors or in the shade (in a well-ventilated place)
Doors Closed
Door windows Open
Hood Open
TEMP. Max. COLD
Mode switch
(Ventilation) set
Intake switch
(Recirculation) set
Fan (blower) speedMax. speed set
Engine speed Idle speed
Operate the air conditioning system for 10 minutes before taking measurements.
Inside air (Recirculating air) at blower assembly inlet
Discharge air temperature at center ventilator
°C (°F) Relative humidity
%Air temperature
°C (°F)
50 - 6020 (68) 5.5 - 7.2 (42 - 45)
25 (77) 8.5 - 10.9 (47 - 52)
30 (86) 12.3 - 15.1 (54 - 59)
35 (95) 16.5 - 19.8 (62 - 68)
40 (104) 21.0 - 25.0 (70 - 77)
60 - 7020 (68) 7.2 - 9.0 (45 - 48)
25 (77) 10.9 - 13.4 (52 - 56)
30 (86) 15.1 - 18.0 (59 - 64)
35 (95) 19.8 - 23.0 (68 - 73)
40 (104) 25.0 - 29.0 (77 - 84)
Ambient air
High-pressure (Discharge side)
kPa (kg/cm
2 , psi)Low-pressure (Suction side)
kPa (kg/cm2 , psi) Relative humidity
%Air temperature
°C (°F)
50 - 7020 (68)733 - 895
(7.5 - 9.1, 106.3 - 129.8)180 - 220
(1.8 - 2.2, 26.1 - 31.9)
25 (77)838 - 1,025
(8.5 - 10.5, 121.5 - 148.6)210 - 257
(2.1 - 2.6, 30.5 - 37.3)
30 (86)985 - 1,204
(10.0 - 12.3, 142.8 - 174.6)239 - 293
(2.4 - 3.0, 34.7 - 42.5)
35 (95)1,115 - 1,363
(11.4 - 13.9, 161.7 - 197.6)270 - 330
(2.8 - 3.4, 39.2 - 47.9)
40 (104)1,294 - 1,581
(13.2 - 16.1, 187.6 - 229.2)331 - 405
(3.4 - 4.1, 48.0 - 58.7)

ATC-106
TROUBLE DIAGNOSIS
Revision: 2007 April2007 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 PG-114, "
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