Page 2465 of 3171
MTC-78
TROUBLE DIAGNOSIS
Blower Motor Resistor
Check continuity between terminals. There will be resistance, but
there should not be an open or short between any two terminals.
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TROUBLE DIAGNOSIS
MTC-79
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Magnet Clutch CircuitEJS005GL
SYMPTOM: Magnet clutch does not engage.
INSPECTION FLOW
*1MTC-53, "Operational Check"*2MTC-51, "A/C System Self-diagnosis
Function".*3MTC-52, "
SELF-DIAGNOSIS CODE
CHART".
*5MTC-95, "
Intake Sensor Circuit".
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MTC-80
TROUBLE DIAGNOSIS
SYSTEM DESCRIPTION
The front air control controls compressor operation based on intake temperature and a signal from ECM.
Low Temperature Protection Control
The front air control will turn the compressor ON or OFF as determined by a signal detected by the intake sen-
sor.
When intake air temperature is higher than the preset value, the compressor turns ON. The compressor turns
OFF when intake air temperature is lower than the preset value. That preset value is dependent on the ambi-
ent temperature, refer to the following table.
DIAGNOSTIC PROCEDURE FOR MAGNET CLUTCH
SYMPTOM: Magnet clutch does not engage when A/C switch is ON.
1.CHECK INTAKE SENSOR CIRCUIT
Check intake sensor. Refer toMTC-95, "
Intake Sensor Circuit".
OK or NG
OK >> GO TO 2.
NG >> Malfunctioning tintake sensor. Refer toMTC-99, "
INTAKE SENSOR".
Ambient temperature°C(°F)Compressor ON
intake temperature C (°F)Compressor OFF
intake temperature C (°F)
0 (32) 5.5 (42) 5.0 (41)
10 (50) 4.5 (40) 4.5 (40)
20 (68) 2.5 (37) 2.0 (36)
30 (86) 2.0 (36) 1.5 (35)
40 (104) 2.0 (36) 1.5 (35)
50 (122) 2.0 (36) 1.5 (35)
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TROUBLE DIAGNOSIS
MTC-81
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2.PERFORM AUTO ACTIVE TEST
Refer toPG-19, "
Auto Active Test".
Does magnet clutch operate?
YES or NO
YES >>lWITH CONSULT-II
GO TO 5.
lWITHOUT CONSULT-II
GO TO 6.
NO >> Check 10A fuse (No. 42, located in IPDM E/R), 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 (magnet
clutch) connector.
3. Check continuity between IPDM E/R harness connector E12 ter-
minal 11 and compressor harness connector F20 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 >> Replace IPDM E/R.
NG >> Replace magnet clutch. Refer toMTC-123, "
Removal
and Installation for Compressor Clutch".
5.CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
Check compressor ON/OFF signal. Refer toBCS-14, "
CONSULT-II
Function (BCM)".
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
11 – 1 : Continuity should exist.
WJIA0560E
SJIA0197E
A/C SW ON : COMP ON SIG ON
A/CSWOFF :COMPONSIGOFF
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MTC-82
TROUBLE DIAGNOSIS
6.CHECK CIRCUIT CONTINUITY BETWEEN BCM AND FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect BCM connector and front air control connector.
3. Check continuity between BCM harness connector M42 terminal
27 and front air control harness connector M98 terminal 10.
OK or NG
OK >> GO TO 7.
NG >> Repair harness or connector.
7.CHECK VOLTAGE FOR FRONT AIR CONTROL (COMPRESSOR ON SIGNAL)
1. Reconnect BCM connector and front air control connector.
2. Turn ignition switch ON.
3. Check voltage between front air control harness connector M98
terminal 10 and ground.
OK or NG
OK >> GO TO 8.
NG-1 >> If the voltage is approx. 5V when A/C switch is ON, replace front air control. Refer toMTC-98,
"CONTROL UNIT".
NG-2 >> If the voltage is approx. 0V when A/C switch is OFF, replace BCM. Refer toBCS-17, "
Removal
and Installation of BCM". 27 - 10 Continuity should exist.
MJIB0107E
Terminals
Condition Voltage (+)
(-) Front air
control con-
nectorTerminal No.
M98 10 GroundA/C switch: ON Approx. 0V
A/C switch: OFF Approx. 5V
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TROUBLE DIAGNOSIS
MTC-83
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8.CHECK REFRIGERANT PRESSURE SENSOR
WITH CONSULT-II
1. Start engine.
2. Check voltage of refrigerant pressure sensor. Refer toBCS-14, "
CONSULT-II Function (BCM)".
WITHOUT CONSULT-II
1. Start engine.
2. Check voltage between ECM harness connector F1 terminal 53
and ground.
OK or NG
OK >>lWITH CONSULT-II
GO TO 9.
lWITHOUT CONSULT-II
GO TO 10.
NG >> Refer toEC-325, "
REFRIGERANT PRESSURE SENSOR".
9.CHECK BCM INPUT (FAN ON) SIGNAL
Check FAN ON/OFF signal. Refer toBCS-14, "
CONSULT-II Func-
tion (BCM)".
OK or NG
OK >> GO TO 12.
NG >> GO TO 10.
Terminals
Condition Voltage (+)
(-)
ECM
connectorTerminal No.
F1 53 Ground A/C switch: ON Approx. 0.36 - 3.88V
MJIB0071E
BLOWER CONTROL
SWITCH ON: FAN ON SIG ON
BLOWER CONTROL
SWITCH OFF:FANONSIGOFF
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MTC-84
TROUBLE DIAGNOSIS
10.CHECK CIRCUIT CONTINUITY BETWEEN BCM, FRONT AIR CONTROL AND BLOWER SWITCH
1. Turn ignition switch OFF.
2. Disconnect BCM connector and front air control connector and
blower switch.
3. Check continuity between BCM harness connector M42 terminal
26 and blower switch M59 terminal 2 and between front air con-
trol harness connector M98 terminal 18 and blower switch M59
terminal 8.
OK or NG
OK >> GO TO 11.
NG >> Repair harness or connector.
11 .CHECK VOLTAGE FOR BCM(FAN ON SIGNAL) AND FRONT AIR CONTROL(BLOWER MONITOR
SIGNAL)
1. Reconnect BCM connector and front air control connector and
blower switch.
2. Turn ignition switch ON.
3. Check voltage between the following terminals.
OK or NG
OK >> GO TO 12.
NG-1 >> If the voltage is approx.12V when blower motor is ON,
replace blower switch. Refer toMTC-98, "
CONTROL
UNIT".
NG-2 >> If the voltage is approx. 0V when blower motor is OFF,
replace BCM. Refer toBCS-17, "
Removal and Installa-
tion of BCM".
NG-3 >> If the voltage is less than 12V when blower motor is ON, replace front air control. Refer toMTC-
98, "CONTROL UNIT". 26 - 2 Continuity should exist.
18 - 8 Continuity should exist.
MJIB0109E
Terminals
Condition Voltage (+)
(-)
Connector Terminal No.
BCM
M4226
GroundA/C switch: ON
Blower motor
operatesApprox. 0V
A/C switch: OFF Approx. 12V
Front air control
M9818A/C switch: ON
Blower motor
operatesLess than
12V
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TROUBLE DIAGNOSIS
MTC-85
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12.CHECK SELF-DIAGNOSTIC RESULT
Perform self-diagnosis. Refer toAT C - 5 5 , "
A/C System Self-diagnosis Function"
OK or NG
OK >> Inspection End.
NG >> Refer toAT C - 5 6 , "
SELF-DIAGNOSIS CODE CHART".
COMPONENT INSPECTION
Refrigerant Pressure Sensor
The refrigerant pressure sensor is attached to the condenser.
MJIB0197E