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ATC-94
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
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 compressor ON or OFF as determined by a signal detected by ambient
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
RJIA4078E
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TROUBLE DIAGNOSIS
ATC-95
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Revision: 2007 April2007 M35/M45
1. CHECK AMBIENT SENSOR AND INTAKE SENSOR CIRCUIT
Check ambient sensor and intake sensor. Refer to AT C - 5 7 , "
FUNCTION CONFIRMATION PROCEDURE" ,
see No. 9 and 11.
OK or NG
OK >> GO TO 2.
NG >>
Malfunctioning ambient sensor: Refer to AT C - 11 2 , "Ambient Sensor Circuit" .
Malfunctioning intake sensor: Refer to ATC-121, "Intake Sensor Circuit" .
2. PERFORM AUTO ACTIVE TEST
Refer to PG-23, "
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-28, "
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 34 and compressor harness connector F24 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 7 , "
FUNCTION
CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-4. Confirm that magnet clutch opera-
tion normal.
NG >> 1. Replace compressor.
2. Go to self-diagnosis procedure AT C - 5 7 , "
FUNCTION
CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-4. Confirm that magnet clutch operation normal.
34 – 1 : Continuity should exist.
RJIA4079E
RJIA2005E
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ATC-96
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
5. CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
Check compressor ON/OFF signal. Refer to AT C - 4 0 , "
CONSULT-II
Function (ECM)" .
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
6. CHECK REFRIGERANT PRESSURE SENSOR
WITH CONSULT-II
1. Start the engine.
2. Check voltage of refrigerant pressure sensor. Refer to EC-138, "
CONSULT-II Reference Value in Data
Monitor" (VQ35DE) or EC-841, "CONSULT-II Reference Value in Data Monitor" (VK45DE).
WITHOUT CONSULT-II
1. Start the engine.
2. Check voltage between ECM harness connector F108 terminal
70 and ground.
OK or NG
OK >>WITH CONSULT-II: GO TO 7.
WITHOUT CONSULT-II: Repair harness or connector.
NG >> Refer to EC-704, "
REFRIGERANT PRESSURE SENSOR" (VQ35DE) or EC-1424, "REFRIGER-
ANT PRESSURE SENSOR" (VK45DE).
7. CHECK ECM INPUT (FAN ON) SIGNAL
Check FAN ON/OFF signal. Refer to AT C - 4 0 , "
CONSULT-II Function
(ECM)" .
OK or NG
OK >> GO TO 8.
NG >> Repair harness or connector.A/C SW ON : AIR COND SIG ON
A/C SW OFF : AIR COND SIG OFF
RJIA3646E
Terminals
Condition Voltage (+)
(−)
ECM
connectorTerminal
No.
F108 70 GroundA/C switch: ON
(Blower motor operates.)Approx. 1.0 -
4.0 V
PBIB1188E
FAN SW ON : HEATER FAN SW ON
FAN SW OFF : HEATER FAN SW OFF
RJIA3646E
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TROUBLE DIAGNOSIS
ATC-97
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Revision: 2007 April2007 M35/M45
8. CHECK CAN COMMUNICATION
Check CAN communication. Refer to EC-161, "
DTC U1000, U1001 CAN COMMUNICATION LINE"
(VQ35DE) or EC-865, "DTC U1000, U1001 CAN COMMUNICATION LINE" (VK45DE).
ECM – IPDM E/R
ECM – Unified meter and A/C amp.
OK or NG
OK >> Replace ECM.
NG >> Repair or replace malfunctioning part(s).
COMPONENT INSPECTION
Refrigerant Pressure Sensor
The refrigerant pressure sensor is attached to the liquid tank.
Make sure that the A/C refrigerant pressure and the sensor output
voltage are within the specified range as shown in the A/C operating
condition figure. Refer to EC-704, "
REFRIGERANT PRESSURE
SENSOR" (VQ35DE) or EC-1424, "REFRIGERANT PRESSURE
SENSOR" (VK45DE).
RJIA4080E
RJIA2954E
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ATC-98
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
Insufficient CoolingNJS000GV
SYMPTOM: Insufficient cooling
INSPECTION FLOW
SJIA1777E
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TROUBLE DIAGNOSIS
ATC-99
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Revision: 2007 April2007 M35/M45
*1ATC-57, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 2 to 6.*2ATC-82, "
Air Mix Door Motor Circuit"*3ATC-102, "Test Reading
(VQ35DE)" or ATC-103, "Test
Reading (VK45DE)"
*4ATC-63, "AUXILIARY MECHA-
NISM: TEMPERATURE SETTING
TRIMMER"
*5ATC-57, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13.*6ATC-71, "
LAN System Circuit"
*7ATC-88, "Blower Motor Circuit"*8ATC-93, "Magnet Clutch Circuit"*9ATC-100, "PERFORMANCE TEST
DIAGNOSIS"
*10ATC-65, "Operational Check"*11AT C - 7 , "CONTAMINATED REFRIG-
ERANT"
*12EM-16, "Checking Drive Belts"
(VQ35DE) or EM-174, "
Checking
Drive Belts" (VK45DE)
*13EC-499, "
SYSTEM DESCRIPTION"
(VQ35DE) or EC-1214, "
SYSTEM
DESCRIPTION" (VK45DE)
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ATC-100
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
PERFORMANCE TEST DIAGNOSIS
*1ATC-102, "PERFORMANCE
CHART"
*2ATC-102, "PERFORMANCE
CHART"
*3ATC-104, "TROUBLE DIAGNOSIS
FOR UNUSUAL PRESSURE"
*4ATC-82, "Air Mix Door Motor Circuit"
SJIA1226E
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TROUBLE DIAGNOSIS
ATC-101
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Revision: 2007 April2007 M35/M45
*1ATC-156, "Check Disc to Pulley
Clearance"
*2ATC-88, "Blower Motor Circuit"*3EM-16, "Checking Drive Belts"
(VQ35DE) or EM-174, "
Checking
Drive Belts" (VK45DE)
SJIA1642E