2008 INFINITI FX35 sensor

ATC-24
< SERVICE INFORMATION >
AIR CONDITIONER CONTROL
AIR CONDITIONER CONTROL
Description of Air Conditioner LAN Control SystemINFOID:0000000001328167
The LAN (Local Area Network) syst em consists of unified meter and A/C amp., mode door motor, air mix door
motors and intake door motor.
A configuration of these component s is shown in the figure below.
System ConstructionINFOID:0000000001328168
A small network is constructed between the unifi ed meter and A/C amp., air mix door motors, mode door
motor and intake door motor. The unified meter and A/C amp. and motors are connected by data transmission
lines and motor power supply lines. The LAN network is built through the ground circuits of each door motor.
Addresses, motor opening angle signals, motor stop si gnals and error checking messages are all transmitted
through the data transmission lines connecting the unified meter and A/C amp. and each door motor.
The following functions are contained in LCUs built into the air mix door motors, the mode door motor and the
intake door motor.
 Address
 Motor opening angle signals
 Data transmission
 Motor stop and drive decision
 Opening angle sensor (PBR function)
 Comparison
 Decision (Unified meter and A/C amp. indicated value and motor opening angle comparison)
OPERATION
The unified meter and A/C amp. receives data from each of the sensors. The unified meter and A/C amp.
sends mode door, air mix door and intake door opening angle data to the mode door motor LCU, air mix door
motor LCU and intake door motor LCU.
The mode door motor, air mix door motors and intake door motor read their respective signals according to the
address signal. Opening angle indication signals received from the unified meter and A/C amp. and each of
the motor position sensors is compared by the LCUs in each door motor with the existing decision and open-
ing angles. Subsequently, HOT/COLD, DEF/VENT and FRE/ REC operation is selected. The new selection
data is returned to the unified meter and A/C amp.
SJIA1609E
RJIA1747E
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ATC-26
< SERVICE INFORMATION >
AIR CONDITIONER CONTROL
The air mix doors are automatically controlled so that in-vehicle temperature is maintained at a predetermined
value by the temperature setting, ambient temper ature, in-vehicle temperature and amount of sunload.
FAN SPEED CONTROL
Blower speed is automatically controlled by the temperature setting, ambient temperature, in-vehicle tempera-
ture, intake temperature, amount of sunload and air mix door position.
With pressing AUTO switch, the blower motor starts to gradually increase air flow volume.
When engine coolant temperature is low, the blower moto r operation is delayed to prevent cool air from flow-
ing.
INTAKE DOOR CONTROL
The intake doors are automatically controlled by the tem perature setting, ambient temperature, in-vehicle tem-
perature, intake temperature, amount of s unload and ON/OFF operation of the compressor.
MODE DOOR CONTROL
The mode door is automatically controlled by the temperat ure setting, ambient temperature, in-vehicle temper-
ature, intake temperature and amount of sunload.
MAGNET CLUTCH CONTROL
When A/C switch, AUTO switch or DEF switch is pr essed, unified meter and A/C amp. transmits compressor
ON signal to BCM.
BCM sends compressor ON signal to ECM, via CAN communication.
ECM judges whether compressor can be turned ON, based on each sensor status (refrigerant-pressure sen-
sor signal, throttle angle, etc.). If it judges compre ssor can be turned ON, it sends compressor ON signal to
IPDM E/R, via CAN communication.
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, ECM simultaneously sends com-
pressor feedback signal to unified meter and A/C amp. via CAN communication.
Unified meter and A/C amp., then, uses input compressor feedback signal to control air inlet.
SELF-DIAGNOSIS SYSTEM
The self-diagnosis system is built into the unified mete r and A/C amp. to quickly locate the cause of malfunc-
tions.
RJIA1957E
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AIR CONDITIONER CONTROLATC-27
< SERVICE INFORMATION >
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Description of Control SystemINFOID:0000000001328169
The control system consists of input sensors, swit ches, the unified meter and A/C amp. (microcomputer) and
outputs. The relationship of these co mponents is shown in the figure below:
Control OperationINFOID:0000000001328170
DISPLAY SCREEN
The operation status of the system is displayed on the screen.
AUTO SWITCH
 The compressor, intake doors, air mix doors, mode doors and blower speed are automatically controlled so
that the in-vehicle temperature will reach, and be mainta ined at the set temperature selected by the operator.
SJIA1658E
SJIA1567E
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ATC-42
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Auto Amp. Terminal and Reference Value
INFOID:0000000001328180
Measure voltage between each terminal and ground by referring 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.
SJIA1566E
RJIA1966E
Te r m i n a l
No. Wire
color ItemIgnition
switch Condition Vo l ta g e
(V)
1LCAN-H — — —
11 P C A N - L — — —
21 R/W Power supply from BAT OFF — Battery voltage
22 W Power supply from IGN ON — Battery voltage
29 B Ground (Power) ON — Approx. 0
30 B Ground ON — Approx. 0
35 LG Power supply from ACC ACC — Battery voltage
39 Y Ambient sensor — — —
40 BR/W In-vehicle sensor — — —
41 P Intake sensor — — —
42 R/Y Compressor ON signal ON A/C switch: ON
(Blower motor operates.)
Approx. 0
OFF switch: ON
(A/C system: OFF)
SJIA1423J
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TROUBLE DIAGNOSISATC-43
< SERVICE INFORMATION >
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Self-Diagnosis FunctionINFOID:0000000001328181
DESCRIPTION
The self-diagnosis system diagnoses sensors, door motors, blower motor, etc. by system line. Refer to appli-
cable sections (items) for details. Shifting from norma l control to the self-diagnosis system is accomplished by
starting the engine (turning the ignition switch ON) and pr essing 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 turn ing the ignition switch OFF. Shifting from one step is
accomplished by means of pressi ng temperature control switch (driver side), as required.
43 G/B A/C LAN signal ON —
45 PU/WECV (Electric Control Valve)
signal ONSelf-diagnosis. STEP-4
(Code No. 45)
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 speed (man-
ual)
54 Y/R Power supply for each door
motor ON — Battery voltage
57 BR/Y Blower motor ON signal ON A/C switch: ON
(Blower motor operates.)
Approx. 0
OFF switch: ON
(A/C system: OFF)
Te r m i n a l
No. Wire
color ItemIgnition
switch Condition Vol tag e
(V)
SJIA1453J
SJIA1607E
SJIA1454J
SJIA1474J
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ATC-44
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Shifting from STEP-5 to AUXILIARY MECHANISM is accomplished by means of pressing (fan) UP switch.
FUNCTION CONFIRMATION PROCEDURE
1.SET IN SELF-DIAGNOSIS MODE
1. Turn ignition switch ON.
2. Set in self-diagnosis mode as follows. Within 10 seconds after starting engine (ignition switch is turned ON.), press OFF switch for at least 5 seconds.
NOTE:
 If battery voltage drops below 12 V during diagnosis STEP-3, door motor speed becomes slower and as a
result, the system may generate an error even when operation is normal. 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 function.
>> GO TO 2.
2.STEP-2: SENSOR CIRCUITS ARE CHECK ED FOR OPEN OR SHORT CIRCUIT
SJIA1571E
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ATC-46
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Refer to the following chart and check discharge air flow, air temper-
ature, blower motor duty ratio and compressor operation.
Checks must be made visually, by listening the sound, or by touching air outlets with hand, etc. for improper
operation.
*1: FOOT position during automatic control. Refer to "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 ATC-57, "
Mode Door Motor Circuit".
 Intake door does not change. Go to Intake Door Motor Circuit. Refer to ATC-62, "
Intake Door Motor Circuit".
 Discharge air temperature does not change. Go to Air Mix Door Motor Circuit. Refer to ATC-59, "
Air Mix Door Motor Circuit".
 Blower motor operation is malfunctioning.
Go to Blower Motor Circuit. Refer to ATC-64, "
Blower Motor Circuit".
 Magnet clutch does not engage. Go to Magnet Clutch Circuit. Refer to ATC-69, "
Magnet Clutch Circuit".
8.STEP-5: TEMPERATURE OF EACH SENSOR IS CHECKED
1. Press temperature control (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 the temperature indicated on the display greatly differs from the
actual temperature, check sensor circuit first, and then check sensor.
OK or NG
OK >> GO TO 10.
NG >> Go to Ambient Sensor Circuit. Refer to ATC-86, "
Ambi-
ent Sensor Circuit".
SJIA0302E
Code No. 414243444546
Mode door position VENT B/L 1 B/L 2
FOOT
*1D/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 motor duty ratio 37% 91% 65% 65% 65% 91%
Compressor ON ON OFF OFF ON ON
Electronic control valve
(ECV) duty ratio 100% 100% 0% 0% 50% 100%
PJIA0151E
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TROUBLE DIAGNOSISATC-47
< SERVICE INFORMATION >
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10.CHECK IN-VEHICLE SENSOR
Press (DEF) switch for the second time. Temperature detected
by in-vehicle sensor is indicated on the display.
NOTE:
If the temperature indicated on the display greatly differs from the
actual temperature, check sensor circuit first, and then check sensor.
OK or NG
OK >> GO TO 11.
NG >> Go to In-vehicle Sensor Circuit. Refer to ATC-88, "
In-
vehicle Sensor Circuit".
11 .CHECK INTAKE SENSOR
Press (DEF) switch for the third time. Temperature detected by
intake sensor is indicated on the display.
NOTE:
If the temperature indicated on the display greatly differs from the
actual temperature, check sensor circuit first, and then check sensor.
OK or NG
OK >> GO TO 12.
NG >> Go to Intake Sensor Circuit. Refer to ATC-94, "
Intake
Sensor Circuit".
12.CHECK CAN COMMUNICATION ERROR
1. Press intake switch.
2. CAN communication error between the unified meter and A/C amp. and the display control unit can be detected as self-diag-
nosis results. (If plural errors occur, the display of each error will
blink twice for 0.5 second intervals.)
OK or NG
OK >> 1. Turn ignition switch OFF or AUTO switch ON. 2. INSPECTION END
NG >> Go to CAN communication. Refer to BCS-11, "
CON-
SULT-III Function (BCM)".
 Unified meter and A/C amp. - Display control unit
13.CHECK MALFUNCTIONING SENSOR AND DOOR MOTOR
Refer to the following chart for malfunctioning code No.
(If two or more sensors and door motors malfuncti on, corresponding code Nos. indicates 1 second each.)
*1: Perform self-diagnosis STEP-2 under sunshine.
PJIA0152E
PJIA0153E
SJIA1611E
Code No. Malfunctioning sensor and door motor (Including circuits) Reference page 21 / −21 Ambient sensor ATC-86, "
Ambient Sensor Circuit"
22 / −22 In-vehicle sensor AT C - 8 8 , "In-vehicle Sensor Circuit"
24 / −24 Intake sensor AT C - 9 4 , "Intake Sensor Circuit"
25 / −25
Sunload sensor*1AT C - 9 1 , "Sunload Sensor Circuit"
26 / −26 Air mix door motor PBR (Driver side)
AT C - 6 2 , "Air Mix Door Motor PBR Circuit"27 / −27 Air mix door motor PBR (Passenger side)
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