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ATC-34
AIR CONDITIONER CONTROL
Revision: 2006 December 2006 FX35/FX45
Description of Control SystemNJS000DO
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 OperationNJS000DP
SJIA1658E
SJIA1567E
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ATC-50
TROUBLE DIAGNOSIS
Revision: 2006 December 2006 FX35/FX45
Auto Amp. Terminals and Reference ValueNJS000DZ
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 Item
Ignition
switch Condition
Voltag e
(V)
1 L CAN-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)
43 G/B A/C LAN signal ON —
SJIA1423J
SJIA1453J
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TROUBLE DIAGNOSIS ATC-51
C
D E
F
G H
I
K L
M A
B
AT C
Revision: 2006 December 2006 FX35/FX45
45 PU/W ECV (Electric Control Valve)
signal ON
Self-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 step
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)
Terminal
No. Wire
color ItemIgnition
switch Condition Voltage
(V)
SJIA1607E
SJIA1454J
SJIA1474J
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ATC-52
TROUBLE DIAGNOSIS
Revision: 2006 December 2006 FX35/FX45
Self-diagnosis FunctionNJS000E0
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 usual control to the self-diagnosis 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 control switch (driver side), as required.
Shifting from STEP-5 to AUXILIARY MECHANISM is accomplished by means of pressing (fan) UP switch
(driver side).
SJIA1571E
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TROUBLE DIAGNOSIS ATC-53
C
D E
F
G H
I
K L
M A
B
AT C
Revision: 2006 December 2006 FX35/FX45
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.
CAUTION:
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 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 control (UP) switch (driver side).
Advance to self
-diagnosis STEP-3?
YES >> GO TO 4.
NO >> Replace A/C and AV switch. (Temperature control switch is malfunctioning.)
4. CHECK TO RETURN SELF-DIAGNOSIS STEP-2
Press temperature control (DOWN) switch (driver side).
Return to self
-diagnosis STEP-2?
YES >> GO TO 5.
NO >> Malfunctioning A/C and AV switch or unified meter and A/C amp. Refer to ATC-101, "
Self-diagno-
sis" .
5. STEP-3: MODE DOOR AND INTAKE DOOR POSITIONS ARE CHECKED
Press temperature control (UP) switch (driver side).
Does code No. 30 appear on the display?
YES >> GO TO 6.
NO >> GO TO 14.
RJIA0219E
RJIA0220E
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TROUBLE DIAGNOSIS ATC-55
C
D E
F
G H
I
K L
M A
B
AT C
Revision: 2006 December 2006 FX35/FX45
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-103, "
Ambi-
ent Sensor Circuit" .
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-106, "
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 AT C - 11 2 , "
Intake
Sensor Circuit" .
SJIA1572E
SJIA1573E
SJIA1574E
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ATC-56
TROUBLE DIAGNOSIS
Revision: 2006 December 2006 FX35/FX45
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-14, "
CAN
Communication Inspection Using CONSULT-II (Self-
Diagnosis)" .
Unified meter and A/C amp. - Display control unit
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 60 W) at sunload sensor, otherwise code No. 25 will indicate
despite that sunload sensor is functioning properly.
*2: ATC-103, "
DIAGNOSIS PROCEDURE FOR AMBIENT SENSOR" .
*3: ATC-107, "
DIAGNOSIS PROCEDURE FOR IN-VEHICLE SENSOR" .
*4: AT C - 11 2 , "
DIAGNOSIS PROCEDURE FOR INTAKE SENSOR" .
*5: ATC-109, "
DIAGNOSIS PROCEDURE FOR SUNLOAD SENSOR" .
*6: AT C - 7 3 , "
DIAGNOSIS PROCEDURE FOR AIR MIX DOOR MOTOR PBR" .
>> INSPECTION END
SJIA1611E
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)
SJIA1641E
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ATC-62
TROUBLE DIAGNOSIS
Revision: 2006 December 2006 FX35/FX45
Power Supply and Ground Circuit for Auto Amp.NJS000E2
SYMPTOM: A/C system does not come on.
INSPECTION FLOW
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.
When the various switches and temperature control switch are oper-
ated, data is input to the unified meter and A/C amp. from the display
control unit using CAN communication.
Self-diagnosis functions are also built into unified meter and A/C
amp. to provide quick check of malfunctions in the auto air condi-
tioner system.
*1 ATC-63, "DIAGNOSIS PROCE-
DURE FOR A/C SYSTEM"
*2 ATC-60, "Operational Check"*3AV-84, "Unable to Operate System
with A/C and AV Switch" (Without
navigation system) or AV-139,
"Unable to Operate System with A/C
and AV Switch" (With navigation
system)
SJIA1582E
SJIA1566E