Page 479 of 4366

AIR CONDITIONER CONTROL ATC-33
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AT C
Revision: 2006 July 2007 FX35/FX45
MAGNET CLUTCH CONTROL
When A/C switch, AUTO switch or DEF switch is pressed, 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 compressor 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 meter and A/C amp. to quickly locate the cause of malfunc-
tions.
RJIA1957E
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TROUBLE DIAGNOSIS ATC-41
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AT C
Revision: 2006 July 2007 FX35/FX45
SYMPTOM TABLE
Symptom Reference Page
A/C system does not come on. Go to Trouble Diagnosis Procedure for A/C System. ATC-62, "
Power
Supply and Ground
Circuit for Auto
Amp."
A/C system cannot be controlled.Go to Integrated Display System.
Go to Navigation System. AV- 8 4 , "
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 navi-
gation system)
Air outlet does not change. Go to Trouble Diagnosis Procedure for Mode Door Motor. (LAN) ATC-68, "
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) AT C - 7 1 , "
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) AT C - 7 4 , "
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-77, "
Blower
Motor Circuit"
Magnet clutch does not engage. Go to Trouble Diagnosis Procedure for Magnet Clutch.AT C - 8 2 , "Magnet
Clutch Circuit"
Insufficient cooling Go to Trouble Diagnosis Procedure for Insufficient Cooling.
ATC-90, "
Insufficient
Cooling"
Go to Diagnosis Procedure for Insufficient Cooling. ATC-97, "
DIAGNO-
SIS PROCEDURE
FOR INSUFFI-
CIENT COOLING"
Insufficient heating Go to Trouble Diagnosis Procedure for Insufficient Heating.
ATC-99, "Insufficient
Heating"
Noise Go to Trouble Diagnosis Procedure for Noise.
ATC-100, "Noise"
Self-diagnosis cannot be performed. Go to Trouble Diagnosis Procedure for Self-diagnosis. ATC-101, "Self-
diagnosis"
Memory function does not operate. Go to Trouble Diagnosis Procedure for Memory Function.
ATC-102, "Memory
Function"
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ATC-54
TROUBLE DIAGNOSIS
Revision: 2006 July 2007 FX35/FX45
6. STEP-4: OPERATION OF EACH DOOR MOTOR IS CHECKED
1. Press temperature control (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 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 AT C - 5 9 , "
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 - 6 8 , "
Mode Door Motor Circuit" .
Intake door does not change.
Go to Intake Door Motor Circuit. Refer to AT C - 7 4 , "
Intake Door Motor Circuit" .
Discharge air temperature does not change.
Go to Air Mix Door Motor Circuit. Refer to AT C - 7 1 , "
Air Mix Door Motor Circuit" .
Blower motor operation is malfunctioning.
Go to Blower Motor Circuit. Refer to AT C - 7 7 , "
Blower Motor Circuit" .
Magnet clutch does not engage.
Go to Magnet Clutch Circuit. Refer to AT C - 8 2 , "
Magnet Clutch Circuit" .
SJIA1780E
SJIA0302E
Code No. 41 42 43 44 45 46
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%
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ATC-60
TROUBLE DIAGNOSIS
Revision: 2006 July 2007 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 FRE 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 FRE
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
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TROUBLE DIAGNOSIS ATC-61
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AT C
Revision: 2006 July 2007 FX35/FX45
2. Check for hot air at discharge air outlets.
If NG, go to trouble diagnosis procedure for AT C - 9 9 , "
Insufficient Heating" .
If OK, continue the check.
CHECKING 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 2 , "
Magnet Clutch Circuit" .
If OK, continue the check.
CHECKING AUTO MODE
1. Press AUTO switch and A/C switch.
2. Display should indicate AUTO.
Confirm that discharge air and blower speed will depend on ambient, in-vehicle, and set temperatures.
If NG, go to trouble diagnosis procedure for AT C - 6 2 , "
Power Supply and Ground Circuit for Auto Amp." , then
if necessary, trouble diagnosis procedure for AT C - 8 2 , "
Magnet Clutch Circuit" .
If all operational checks are OK (symptom cannot be duplicated), go to Incident Simulation Tests in GI-28,
"How to Perform Efficient Diagnosis for an Electrical Incident" and perform tests as outlined to simulate driv-
ing conditions environment. If symptom appears, refer to AT C - 4 1 , "
SYMPTOM TABLE" and perform applica-
ble trouble diagnosis procedures.
Page 528 of 4366
ATC-82
TROUBLE DIAGNOSIS
Revision: 2006 July 2007 FX35/FX45
Magnet Clutch CircuitNJS000E9
SYMPTOM: Magnet clutch does not engage.
INSPECTION FLOW
*1ATC-112, "Intake Sensor Circuit"*2 ATC-103, "Ambient Sensor Circuit"*3AT C - 5 3 , "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13.
*4 ATC-83, "
DIAGNOSIS PROCE-
DURE FOR MAGNET CLUTCH"
*5 ATC-95, "TROUBLE DIAGNOSIS
FOR UNUSUAL PRESSURE"
*6AT C - 6 0 , "Operational Check"
*7ATC-53, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 4 to 6. *8
ATC-41, "
SYMPTOM TABLE"
SJIA1590E
Page 529 of 4366
TROUBLE DIAGNOSIS ATC-83
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K L
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AT C
Revision: 2006 July 2007 FX35/FX45
SYSTEM DESCRIPTION
Unified meter and A/C amp. controls compressor operation by ambient temperature, intake air temperature
and signal from ECM.
Low Temperature Protection Control
Unified meter and A/C amp. will turn the compressor ON or OFF as determined by a signal detected by ambi-
ent sensor and intake sensor.
When ambient temperature is higher than −2 °C (28 °F), the compres-
sor turns ON. The compressor turns OFF when ambient temperature
is lower than −5 °C (23 °F).
When intake air temperature is higher than 1 °C (34 °F), the compres-
sor turns ON. The compressor turns OFF when intake air tempera-
ture is lower than −5°C (23 °F).
DIAGNOSIS PROCEDURE FOR MAGNET CLUTCH
SYMPTOM: Magnet clutch does not engage when A/C switch is ON.
RHA094GB
SJIA0267E
SJIA1608E
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ATC-84
TROUBLE DIAGNOSIS
Revision: 2006 July 2007 FX35/FX45
1. CHECK AMBIENT SENSOR AND INTAKE SENSOR CIRCUIT
Check ambient sensor and intake sensor. Refer to AT C - 5 3 , "
FUNCTION CONFIRMATION PROCEDURE" ,
see No. 9 and 11.
OK or NG
OK >> GO TO 2.
NG >>
Malfunctioning ambient sensor: Refer to ATC-103, "Ambient Sensor Circuit" .
Malfunctioning intake sensor: Refer to AT C - 11 2 , "Intake Sensor Circuit" .
2. PERFORM AUTO ACTIVE TEST
Refer to PG-21, "
Auto Active Test" .
Does the magnet clutch operate?
YES >>WITH CONSULT-II: GO TO 5
WITHOUT CONSULT-II: GO TO 6.
NO >> Check 10A fuse (No. 79, located in IPDM E/R). Refer to PG-25, "
IPDM E/R Terminal Arrange-
ment" , and GO TO 3.
3. CHECK CIRCUIT CONTINUITY BETWEEN IPDM E/R AND COMPRESSOR
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R connector and compressor connector.
3. Check continuity between IPDM E/R harness connector E8 ter- minal 33 and compressor harness connector F2 terminal 1.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4. CHECK MAGNET CLUTCH CIRCUIT
Check for operation sound when applying battery voltage direct cur-
rent to terminal.
OK or NG
OK >> 1. Replace IPDM E/R. 2. Go to self-diagnosis procedure AT C - 5 3 , "
FUNCTION
CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-4. Confirm that magnet clutch opera-
tion normal.
NG >> 1. Replace magnet clutch. 2. Go to self-diagnosis procedure AT C - 5 3 , "
FUNCTION
CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-4. Confirm that magnet clutch operation normal.
33 – 1 : Continuity should exist.
RJIA2004E
RJIA2005E