sensor INFINITI FX35 2004 Service Manual

AIR CONDITIONER CONTROL
ATC-33
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Revision: 2004 November 2004 FX35/FX45
MAGNET CLUTCH CONTROL
When A/C switch or DEF switch is pressed, unified meter and A/C amp. inputs compressor ON signal to BCM.
BCM sends compressor ON signal to ECM, via CAN communication line.
ECM judges whether compressor can be turned ON, based on each sensor status (refrigerant-pressure sen-
sor signal, throttle angle, etc.). If it judges compressor can be turned ON, it sends compressor ON signal to
IPDM E/R, via CAN communication line.
Upon receipt of compressor ON signal from ECM, IPDM E/R turns air conditioner relay ON to operate com-
pressor.
When sending compressor ON signal to IPDM E/R via CAN communication line, ECM simultaneously sends
compressor feedback signal to unified meter and A/C amp. via CAN communication line.
Unified meter and A/C amp, then, uses input compressor feedback signal to control air inlet.
SELF-DIAGNOSTIC SYSTEM
The self-diagnostic system is built into the unified meter and A/C amp. to quickly locate the cause of symp-
toms.
RJIA1957E

ATC-34
AIR CONDITIONER CONTROL
Revision: 2004 November 2004 FX35/FX45
Description of Control SystemAJS0014C
The control system consists of input sensors, switches, the unified meter and A/C amp. (microcomputer) and
outputs.
The relationship of these components is shown in the figure below:
Control OperationAJS0014D
RJIA1958E
RJIA1959E

TROUBLE DIAGNOSIS
ATC-51
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Revision: 2004 November 2004 FX35/FX45
Auto Amp. Terminals and Reference ValueAJS0014O
Measure voltage between each terminal and ground by following ter-
minals and reference value for unified meter and A/C amp.
PIN CONNECTOR TERMINAL LAYOUT
TERMINALS AND REFERENCE VALUE FOR UNIFIED METER AND A/C AMP.
RJIA1965E
RJIA1966E
Terminal
No.Wire
colorItemIgnition
switchConditionVoltage
(V)
1 L CAN H - - -
11 R C A N L - - -
21 R/W Power supply for BATT OFF - Battery voltage
22 G/R Power supply for IGN ON - Battery voltage
29 B Ground (Power) ON - Approx. 0
30 B Ground ON - Approx. 0
35 LG/R Power supply for ACC ON - Battery voltage
39 Y Ambient sensor - - -
40 BR/W In-vehicle sensor - - -
41 P Intake sensor - - -
42 R/Y Compressor ON signal ONA/C switch: ON Approx. 0
A/C switch: OFF Approx. 5
43 G/B A/C LAN signal ON -
45 PU/WECV (Electric Control Valve)
signalON -
HAK0652D
RJIA1606E

ATC-52
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
46 L/W Power supply for IGN2 ON - Battery voltage
49 W/G Sensor ground ON - Approx. 0
50 LG Sunload sensor - - -
53 G Blower motor control signal ON Blower speed: 1st step
54 Y/RPower supply for each door
motorON - Battery voltage
57 BR/Y Blower motor ON signal ONA/C switch: ON (Blower motor
operate)Approx. 0
A/C switch: OFF Approx. 5 Te r m i n a l
No.Wire
colorItemIgnition
switchConditionVoltag e
(V)
SJIA0116J

TROUBLE DIAGNOSIS
ATC-53
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Revision: 2004 November 2004 FX35/FX45
Self-diagnosis FunctionAJS0014P
DESCRIPTION
The self-diagnostic system diagnoses sensors, door motors, blower motor, etc. by system line. Refer to appli-
cable sections (items) for details. Shifting from usual control to the self-diagnostic system is accomplished by
starting the engine (turning the ignition switch ON) and pressing OFF switch for at least 5 seconds. The OFF
switch must be pressed within 10 seconds after starting the engine (ignition switch is turned ON). This system
will be canceled by either pressing AUTO switch or turning the ignition switch OFF. Shifting from one step to
another is accomplished by means of pressing temperature switch (driver side), as required.
Additionally shifting from STEP-5 to AUXILIARY MECHANISM is accomplished by means of pressing (fan)
UP switch.
RJIA1967E

ATC-54
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
FUNCTION CONFIRMATION PROCEDURE
1. SET IN SELF-DIAGNOSTIC MODE
1. Turn ignition switch ON.
2. Set in self-diagnostic mode as follows. Within 10 seconds after starting engine (ignition switch is turned
ON.), press OFF switch for at least 5 seconds.
CAUTION:

If battery voltage drops below 12V during diagnosis STEP-3, actuator speed becomes slower and
as a result, the system may generate an error even when operation is usual. To avoid this, start
engine before performing this diagnosis.

Former STEP-1 (LEDs and display screen are checked) does not exist in this self-diagnosis func-
tion.
>> GO TO 2.
2. STEP-2: SENSOR CIRCUITS ARE CHECKED FOR OPEN OR SHORT CIRCUIT
Does code No. 20 appear on the display?
YES >> GO TO 3.
NO >> GO TO 13.
3. CHECK TO ADVANCE SELF-DIAGNOSIS STEP-3
Press temperature (UP) switch (driver side).
Advance to self
-diagnosis STEP-3?
YES >> GO TO 4.
NO >> Malfunctioning OFF switch or unified meter and A/C amp. Refer to ATC-102, "
Self-diagnosis" .
4. CHECK TO RETURN SELF-DIAGNOSIS STEP-2
Press temperature (DOWN) switch (driver side).
Return to self
-diagnosis STEP-2?
YES >> GO TO 5.
NO >> Replace A/C and AV switch. Temperature switch malfunctions.
5. STEP-3: MODE DOOR AND INTAKE DOOR POSITIONS ARE CHECKED
Press temperature (UP) switch (driver side).
Does code No. 30 appear on the display?
YES >> GO TO 6.
NO >> GO TO 14.
RJIA0219E
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ATC-56
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
8. STEP-5: TEMPERATURE OF EACH SENSOR IS CHECKED
1. Press temperature (UP) switch (driver side).
2. Code No. 51 appears on the display.
>> GO TO 9.
9. CHECK AMBIENT SENSOR
Press (DEF) switch one time. Temperature detected by ambient
sensor is indicated on the display.
NOTE:
If temperature shown on display greatly differs from actual tempera-
ture, check sensor circuit first, then inspect sensor.
OK or NG
OK >> GO TO 10.
NG >> Go to Ambient Sensor Circuit. Refer to ATC-104, "
Ambi-
ent Sensor Circuit" .
10. CHECK IN-VEHICLE SENSOR
Press (DEF) switch a second time. Temperature detected by in-
vehicle sensor is indicated on the display.
NOTE:
If temperature shown on display greatly differs from actual tempera-
ture, check sensor circuit first, then inspect sensor.
OK or NG
OK >> GO TO 11.
NG >> Go to In-vehicle Sensor Circuit. Refer to ATC-107, "
In-
vehicle Sensor Circuit" .
11 . CHECK INTAKE SENSOR
Press (DEF) switch a third time. Temperature detected by intake
sensor is indicated on the display.
NOTE:
If temperature shown on display greatly differs from actual tempera-
ture, check sensor circuit first, then inspect sensor.
OK or NG
OK >> GO TO 12.
NG >> Go to Intake Sensor Circuit. Refer to AT C - 11 3 , "
Intake
Sensor Circuit" .
RJIA0223E
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TROUBLE DIAGNOSIS
ATC-57
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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

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-70
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
Mode Door Motor CircuitAJS0014T
SYMPTOM:

Air outlet does not change.

Mode door motor does not operate normally.
INSPECTION FLOW
*1AT C - 3 7 , "Discharge Air Flow".*2ATC-61, "Operational Check".*3ATC-113, "Intake Sensor Circuit".
*4AT C - 5 4 , "
FUNCTION CONFIRMA-
TION PROCEDURE", see No. 4 to 6.*5ATC-104, "
Ambient Sensor Circuit".*6ATC-107, "In-vehicle Sensor Cir-
cuit".
*7AT C - 11 0 , "
Sunload Sensor Circuit".*8ATC-73, "Air Mix Door Motor Cir-
cuit".*9ATC-54, "
FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13.
*10AT C - 6 6 , "
DIAGNOSTIC PROCE-
DURE FOR LAN CIRCUIT".*11ATC-130, "
MODE DOOR MOTOR".*12ATC-42, "SYMPTOM TABLE".
RJIA1991E