2004 INFINITI FX35 air intake

AIR CONDITIONER CONTROL
ATC-35
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2004 November 2004 FX35/FX45
DISPLAY SCREEN
Displays the operational status of the system.
AUTO SWITCH

The compressor, intake doors, air mix doors, outlet doors and blower speed are automatically controlled
so that the in-vehicle temperature will reach, and be maintained at the set temperature selected by the
operator.

When pressing AUTO switch, air inlet, air outlet, fan speed, and discharge air temperature are automati-
cally controlled.
TEMPERATURE SWITCH (POTENTIO TEMPERATURE CONTROL) (DRIVER SIDE)
Increases or decreases the set temperature.
TEMPERATURE SWITCH (POTENTIO TEMPERATURE CONTROL) (PASSENGER SIDE)

Increases or decreases the set temperature.

When the temperature switch is pressed, the dual switch indicator will automatically illuminate.
RECIRCULATION (REC) SWITCH

When REC switch is ON, REC switch indicator turns ON, and air inlet is fixed to REC.

When REC switch is ON and is pressed for approximately 1.5 seconds or longer, REC and FRE switch
indicators blink twice. Then, automatic control mode is entered. Inlet status is displayed even during auto-
matically controlled.

When FRE switch is turned ON, or when compressor is turned from ON to OFF, REC switch is automati-
cally turned OFF (fixed to FRE mode). REC mode can be re-entered by pressing REC switch again.

REC switch is not operated when DEF switch is turned ON, or at the D/F position.
FRESH (FRE) SWITCH

When FRE switch is ON, FRE switch indicator turns ON, and air inlet is fixed to FRE.

When FRE switch is ON and is pressed for approximately 1.5 seconds or longer, REC and FRE switch
indicators blink twice. Then, automatic control mode is entered. Inlet status is displayed even during auto-
matically controlled.

When REC switch is turned ON, FRE switch is automatically turned OFF (fixed to REC mode). FRE mode
can be re-entered by pressing FRE switch again.
DEFROSTER (DEF) SWITCH
Positions the air outlet doors to the defrost position. Also positions the intake doors to the fresh air position.
REAR WINDOW DEFOGGER SWITCH
When illumination is ON, rear window is defogged.
OFF SWITCH
The compressor and blower are OFF, the intake doors are set to the fresh air position, and the air outlet doors
are set to the foot (75% foot and 25% defrost) position.
A/C SWITCH
The compressor is ON or OFF.
(Pressing the A/C switch when the AUTO switch is ON will turn off the A/C switch and compressor.)
MODE SWITCH
Controls the air discharge outlets.
FAN SWITCH
Manually control the blower speed. Seven speeds are available for manual control (as shown on the display
screen).
DUAL SWITCH (WITH LEFT AND RIGHT VENTILATION TEMPERATURE SEPARATELY CON-
TROL SYSTEM)

When the DUAL switch indicator is not illuminated and the DUAL switch is pressed, the driver-side setting
temperature and passenger-side setting temperature can each be set independently.

When the DUAL switch indicator is illuminated and the DUAL switch is pressed, the driver-side setting
temperature are applied to both sides.

ATC-42
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
How to Perform Trouble Diagnosis for Quick and Accurate RepairAJS0014K
WORK FLOW
SYMPTOM TABLE
*1ATC-61, "Operational Check"
SHA900E
Symptom Reference Page
A/C system does not come on. Go to Trouble Diagnosis Procedure for A/C System.AT C - 6 3 , "
Power
Supply and Ground
Circuit for Auto
Amp."
A/C system cannot be controlled.
Go to Integrated Display System.

Go to Navigation System.AV-78, "
Trouble
Diagnosis Chart by
Symptom" (Without
navigation system)
or AV-84, "
A/C and
AV Switch Does Not
Operate" (With nav-
igation system)
Air outlet does not change.
Go to Trouble Diagnosis Procedure for Mode Door Motor. (LAN)AT C - 7 0 , "
Mode
Door Motor Circuit"Mode door motor does not operate normally.
Discharge air temperature does not change.
Go to Trouble Diagnosis Procedure for Air Mix Door Motor.
(LAN)ATC-73, "
Air Mix
Door Motor Circuit"Air mix door motor does not operate nor-
mally.
Intake door does not change.
Go to Trouble Diagnosis Procedure for Intake Door Motor. (LAN)ATC-76, "
Intake
Door Motor Circuit"Intake door motor does not operate nor-
mally.
Blower motor operation is malfunctioning.
Go to Trouble Diagnosis Procedure for Blower Motor.ATC-79, "
Blower
Motor Circuit"Blower motor operation is malfunctioning
under out of starting fan speed control.
Magnet clutch does not engage. Go to Trouble Diagnosis Procedure for Magnet Clutch.ATC-84, "
Magnet
Clutch Circuit"
Insufficient coolingGo to Trouble Diagnosis Procedure for Insufficient Cooling.AT C - 9 1 , "
Insufficient
Cooling"
Go to Diagnostic Procedure for Insufficient Cooling.AT C - 9 8 , "
DIAG-
NOSTIC PROCE-
DURE FOR
INSUFFICIENT
COOLING"
Insufficient heating Go to Trouble Diagnosis Procedure for Insufficient Heating.ATC-100, "Insuffi-
cient Heating"
Noise Go to Trouble Diagnosis Procedure for Noise.ATC-101, "Noise"
Self-diagnosis cannot be performed. Go to Trouble Diagnosis Procedure for Self-diagnosis.ATC-102, "Self-
diagnosis"
Memory function does not operate. Go to Trouble Diagnosis Procedure for Memory Function.ATC-103, "Memory
Function"

TROUBLE DIAGNOSIS
ATC-55
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2004 November 2004 FX35/FX45
6. STEP-4: OPERATION OF EACH DOOR MOTOR IS CHECKED
1. Press temperature (UP) switch (driver side).
2. Press (DEF) switch. Code No. of each door motor test is
indicated on the display.
>> GO TO 7.
7. CHECK ACTUATORS
Refer to the following chart and confirm discharge air flow, air tem-
perature, blower motor voltage and compressor operation.
Checks must be made visually, by listening to any noise, or by touching air outlets with your hand, etc. for
improper operation.
*1: FOOT position during automatic control. Refer to AT C - 6 0 , "
AUXILIARY MECHANISM: FOOT POSITION
SETTING TRIMMER" .
OK or NG
OK >> GO TO 8.
NG >>

Air outlet does not change.
Go to Mode Door Motor Circuit. Refer to AT C - 7 0 , "
Mode Door Motor Circuit" .

Intake door does not change.
Go to Intake Door Motor Circuit. Refer to AT C - 7 6 , "
Intake Door Motor Circuit" .

Blower motor operation is malfunctioning.
Go to Blower Motor Circuit. Refer to AT C - 7 9 , "
Blower Motor Circuit" .

Magnet clutch does not engage.
Go to Magnet Clutch Circuit. Refer to AT C - 8 4 , "
Magnet Clutch Circuit" .

Discharge air temperature does not change.
Go to Air Mix Door Motor Circuit. Refer to AT C - 7 3 , "
Air Mix Door Motor Circuit" .
RJIA1968E
SJIA0302E
41 42 43 44 45 46
Mode door position VENT B/L 1 B/L 2 FOOT*1 D/F DEF
Intake door position REC REC 20%FRE FRE FRE FRE
Air mix door position FULL COLD FULL COLD FULL HOT FULL HOT FULL HOT FULL HOT
Blower fan duty ratio 37% 91% 65% 65% 65% 91%
Compressor ON ON OFF OFF ON ON
Electronic control
valve (ECV) duty
ratio100% 100% 0% 0% 50% 100%

TROUBLE DIAGNOSIS
ATC-57
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2004 November 2004 FX35/FX45
12. CHECK CAN COMMUNICATION ERROR
1. Press (REC) switch.
2. CAN communication error between unified meter and A/C amp.
and DISPLAY UNIT or DISPLAY C/U is detected.
OK or NG
OK >> 1. Turn ignition switch OFF or AUTO switch ON.
2. INSPECTION END
NG >> Go to CAN communication. Refer to BCS-14, "
CAN
Communication Inspection Using CONSULT-II (Self-
Diagnosis)" .

Unified meter and A/C amp. - DISPLAY UNIT

Unified meter and A/C amp. - DISPLAY C/U
13. CHECK MALFUNCTIONING SENSOR
Refer to the following chart for malfunctioning code No.
(If two or more sensors malfunction, corresponding code Nos. blink respectively twice.)
*1: Perform self-diagnosis STEP-2 under sunshine.
When performing indoors, aim a light (more than 60W) at sunload sensor, otherwise code No. 25 will indicate
despite that sunload sensor is functioning properly.
*2: ATC-104, "
DIAGNOSTIC PROCEDURE FOR AMBIENT SENSOR" .
*3: ATC-108, "
DIAGNOSTIC PROCEDURE FOR IN-VEHICLE SENSOR" .
*4: AT C - 11 3 , "
DIAGNOSTIC PROCEDURE FOR INTAKE SENSOR" .
*5: AT C - 11 0 , "
DIAGNOSTIC PROCEDURE FOR SUNLOAD SENSOR" .
*6: AT C - 6 6 , "
DIAGNOSTIC PROCEDURE FOR LAN CIRCUIT" .
>> INSPECTION END
RJIA1969E
Code No. Malfunctioning sensor (Including circuits) Reference page
21 / −21 Ambient sensor *2
22 / −22 In-vehicle sensor *3
24 / −24 Intake sensor *4
25 / −25 Sunload sensor *1 *5
26 / −26 Air mix door motor PBR (Driver side)
*6
27 / −27 Air mix door motor PBR (Passenger side)
RJIA0227E

TROUBLE DIAGNOSIS
ATC-61
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2004 November 2004 FX35/FX45
Operational CheckAJS0014Q
The purpose of the operational check is to confirm that the system operates properly.
CHECKING MEMORY FUNCTION
1. Set the temperature to 32°C (90°F).
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 tempera-
ture.
7. Press OFF switch.
If NG, go to trouble diagnosis procedure for ATC-103, "
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 - 7 9 , "
Blower Motor
Circuit" .
If OK, continue the check.
CHECKING DISCHARGE AIR
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 distri-
bution table. Refer to AT C - 3 7 , "
Discharge Air Flow" .
If NG, go to trouble diagnosis procedure for AT C - 7 0 , "
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 DEF
or D/F is selected.Conditions : Engine running at usual operating temperature
RJIA1972E
RJIA1973E
RJIA1974E
SJIA0302E

ATC-62
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
CHECKING RECIRCULATION
1. Press recirculation (REC) switch one time. Recirculation indica-
tor should illuminate.
2. Press fresh (FRE) switch one time. Fresh indicator should illumi-
nate.
3. Listen for intake door position change (you should hear blower
sound change slightly).
If NG, go to trouble diagnosis procedure for AT C - 7 6 , "
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 DEF or D/F is selected.
CHECKING TEMPERATURE DECREASE
1. Press temperature (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 1 , "
Insufficient
Cooling" .
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Press temperature (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-100, "
Insufficient
Heating" .
If OK, continue the check.
CHECK 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 - 8 4 , "
Magnet Clutch
Circuit" .
If OK, continue the check.
RJIA1978E
RJIA1976E
RJIA1977E
RJIA1975E

ATC-64
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
COMPONENT DESCRIPTION
Unified Meter and A/C amp. (Automatic Amplifier)
The unified meter and A/C amp. has a built-in microcomputer which
processes information sent from various sensors needed for air con-
ditioner operation. The air mix door motor, mode door motor, intake
door motor, blower motor and compressor are then controlled.
The unified meter and A/C amp. is unitized with control mechanisms.
When the various switches and temperature switch are operated,
data is input to the unified meter and A/C amp. from the DISPLAY
UNIT/DISPLAY C/U using CAN communication.
Self-diagnostic functions are also built into unified meter and A/C
amp. to provide quick check of malfunctions in the auto air condi-
tioner system.
Potentio Temperature Control (PTC)
The PTC is built into the A/C and AV switch. It can be set at an inter-
val of 0.5°C (1.0°F) in the 18°C (60°F) to 32°C (90°F) temperature
range by pressing temperature switch. The set temperature is dis-
played.
DIAGNOSTIC PROCEDURE FOR A/C SYSTEM
SYMPTOM: A/C system does not come on.
RJIA1965E
RJIA1982E
RJIA1983E

ATC-66
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
LAN System CircuitAJS0014S
SYMPTOM: Mode door motor, intake door motor and/or air mix door motor(s) does not operate normally.
DIAGNOSTIC 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 M57 terminal 54 (Y/R) 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 M57 terminal 43 (G/B) and ground using an oscillo-
scope.
OK or NG
OK >> GO TO 3.
NG >> Replace unified meter and A/C amp.
RJIA1775E
54 – Ground : Battery voltage
RJIA1986E
Terminals
Voltage (+)
(−)
Unified meter and A/
C amp. connectorTerminal No.
(wire color)
M57 43 (G/B) Ground
RJIA1987E
HAK0652D