Ac system INFINITI FX35 2006 Service Manual

TROUBLE DIAGNOSIS ATC-53
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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

ATC-58
TROUBLE DIAGNOSIS
Revision: 2006 December 2006 FX35/FX45
AUXILIARY MECHANISM: TEMPERATURE SETTING TRIMMER
The trimmer compensates for differences in range of ±3 °C ( ±6°F) between temperature setting (displayed dig-
itally) and temperature felt by customer.
Operating procedures for this trimmer are as follows:
1. Begin self-diagnosis STEP-5 mode. Refer to AT C - 5 2 , "
Self-diagnosis Function" .
2. Press (fan) UP switch to set system in auxiliary mode.
3. Display shows 61 in auxiliary mechanism. It takes approximately 3 seconds to enable setting operation.
4. Press temperature control switch (driver side) as desired. Temperature will change at a rate of 0.5 °C
(1.0 °F) each time a switch is pressed.
CAUTION:
A decimal point is not indicated when the display shows “ °C”.
When battery cable is disconnected or battery voltage is 10 V or less, trimmer operation is canceled. Temper-
ature set becomes that of initial condition, i.e. 0 °C (0 °F).
SJIA1575E

TROUBLE DIAGNOSIS ATC-59
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Revision: 2006 December 2006 FX35/FX45
AUXILIARY MECHANISM: FOOT POSITION SETTING TRIMMER
Wind distribution ratio in FOOT mode can be set.
Operating procedures for this trimmer are as follows:
1. Begin self-diagnosis STEP-5 mode. Refer to AT C - 5 2 , "
Self-diagnosis Function" .
2. Press (fan) UP switch to set system in auxiliary mode.
3. Display shows 61 in auxiliary mechanism. It takes approximately 3 seconds to enable setting operation.
4. Press the mode switch as desired.
When battery cable is disconnected or battery voltage below 10 V, trimmer operation is canceled. Wind distri-
bution ratio set becomes that of initial condition.
AUXILIARY MECHANISM: INLET PORT MEMORY FUNCTION
When ignition switch is turned from OFF to ON, inlet port memory function at manual mode can be set.
Operating procedures for this trimmer are as follows:
1. Begin self-diagnosis STEP-5 mode. Refer to AT C - 5 2 , "
Self-diagnosis Function" .
2. Press (fan) UP switch to set system in auxiliary mode.
3. Display shows 61 in auxiliary mechanism. It takes approximately 3 seconds to enable setting operation.
4. Press the intake switch as desired.
When battery cable is disconnected or battery voltage below 10 V, memory function is canceled. Memory func-
tion set becomes that of initial condition.
SJIA1581E
LED status of
FRE position LED status of
REC position Setting status
Setting changeover
method
FRE REC
OFF OFF AUTO control AUTO control
Intake SW: ON
OFF ON AUTO control (Initial setting)
Manual REC status is memorized.
(Initial setting)
ON OFF Manual FRE status is memorized. AUTO control
ON ON Manual FRE status is memorized. Manual REC status is memorized.

ATC-60
TROUBLE DIAGNOSIS
Revision: 2006 December 2006 FX35/FX45
Operational CheckNJS000E1
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 ATC-102, "
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 7 , "
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 - 6 8 , "
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.
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 - 7 4 , "
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 0 , "
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.
Conditions : Engine running at normal operating temperature
SJIA0302E

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

TROUBLE DIAGNOSIS ATC-63
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Revision: 2006 December 2006 FX35/FX45
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 control switch. The set temperature
is displayed.
DIAGNOSIS PROCEDURE FOR A/C SYSTEM
SYMPTOM: A/C system does not come on.
1. CHECK POWER SUPPLY CIRCUIT FOR UNIFIED METER AND A/C AMP.
1. Disconnect unified meter and A/C amp. connector.
2. Check voltage between unified meter and A/C amp. harness connector M56 terminals 21, 22 and 35, unified meter and A/C
amp. harness connector M57 terminal 46 and ground.
OK or NG
OK >> GO TO 2.
NG >> Check 10A and 15A fuses [Nos. 6, 10, 11, 12 and 19, located in the fuse block (J/B)]. Refer to PG-
81, "FUSE BLOCK - JUNCTION BOX (J/B)" .

If fuses are OK, check harness for open circuit. Repair or replace if necessary.

If fuses are NG, check harness for short circuit and replace fuse.
SJIA1583E
RJIA1983E
Terminals Ignition switch position
(+)
(-) OFF ACC ON
Unified
meter and
A/C amp.
connector Terminal No.
M56 21
Ground Battery volt-
age Battery volt-
age Battery
voltage
M56 22 Approx. 0 V Approx. 0 V Battery
voltage
M56 35 Approx. 0 V Battery volt-
age Battery
voltage
M57 46 Approx. 0 V Battery volt-
age Battery
voltage
RJIA1984E

ATC-64
TROUBLE DIAGNOSIS
Revision: 2006 December 2006 FX35/FX45
2. CHECK GROUND CIRCUIT FOR UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Check continuity between unified meter and A/C amp. harness connector M56 terminal 29, 30 and ground.
OK or NG
OK >> Replace unified meter and A/C amp.
NG >> Repair harness or connector.
LAN System CircuitNJS000E3
SYMPTOM: Mode door motor, intake door motor and/or air mix door motor(s) does not operate normally.
DIAGNOSIS 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 and ground.
OK or NG
OK >> GO TO 2.
NG >> Replace unified meter and A/C amp. 29, 30 – Ground : Continuity should exist.
RJIA1985E
RJIA1775E
54 – Ground : Battery voltage
RJIA1986E

TROUBLE DIAGNOSIS ATC-69
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Revision: 2006 December 2006 FX35/FX45
SYSTEM DESCRIPTION
Component Parts
Mode door control system components are:

Unified meter and A/C amp.

Mode door motor (LCU)

A/C LAN system (PBR built-in mode door motor, air mix door motor and intake door motor)

In-vehicle sensor

Ambient sensor

Sunload sensor

Intake sensor
System Operation
The unified meter and A/C amp. receives data from each of the sensors. The unified meter and A/C amp.
sends air mix door, mode door and intake door opening angle data to the air mix door motor LCU, mode door
motor LCU and intake door motor LCU.
The air mix door motor, mode door motor 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 are 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 are returned to the unified meter and A/C amp.
SJIA1585E

TROUBLE DIAGNOSIS ATC-71
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Revision: 2006 December 2006 FX35/FX45
Air Mix Door Motor CircuitNJS000E5
SYMPTOM

Discharge air temperature does not change.

Air mix door motor does not operate normally.
INSPECTION FLOW
*1 ATC-53, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 4 to 6. *2
ATC-103, "
Ambient Sensor Circuit"*3 ATC-106, "In-vehicle Sensor Circuit"
*4ATC-109, "Sunload Sensor Circuit"*5ATC-71, "Air Mix Door Motor Circuit"*6 ATC-53, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13.
*7 ATC-64, "
LAN System Circuit".*8 ATC-60, "Operational Check"*9ATC-41, "SYMPTOM TABLE"
*10ATC-112, "Intake Sensor Circuit"
SJIA1586E

ATC-72
TROUBLE DIAGNOSIS
Revision: 2006 December 2006 FX35/FX45
SYSTEM DESCRIPTION
Component Parts
Air mix door control system components are:

Unified meter and A/C amp.

Air mix door motor (LCU)

A/C LAN system (PBR built-in mode door motor, air mix door motor and intake door motor)

In-vehicle sensor

Ambient sensor

Sunload sensor

Intake sensor
System Operation
The unified meter and A/C amp. receives data from each of the sensors. The unified meter and A/C amp.
sends air mix door, mode door and intake door motor opening angle data to the air mix door motor LCUs,
mode door motor LCU and intake door motor LCU.
The air mix door motors, mode door motor 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 are 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 are returned to the unified meter and A/C amp.
Air Mix Door Control Specification
RJIA1781E
RJIA1782E