Page 438 of 3502
ATC-60
TROUBLE DIAGNOSIS
3. CHECK POWER SUPPLY FOR EACH DOOR MOTOR
Check voltage between each door motor harness connector M252,
M253, M254 and M255 terminal 1 and ground.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4. CHECK SIGNAL FOR EACH DOOR MOTOR
Confirm A/C LAN signal between each door motor harness connec-
tor terminal 3 and ground using an oscilloscope.
OK or NG
OK >> GO TO 5.
NG >> Repair harness or connector.
5. CHECK MOTOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect each door motor connector.
3. Check continuity between each door motor harness connector
M252, M253, M254 and M255 terminal 2 and ground.
OK or NG
OK >> GO TO 6.
NG >> Repair harness or connector.1 – Ground : Battery voltage
RJIA1988E
Door
motorTe r m i n a l s
Voltage (+)
(-)
Con-
nectorTerminal
No.
Mode M252 3
Ground Air mix
(Driver
side)M253 3
Air mix
(Passen-
ger side)M254 3
Intake M255 3
RJIA1989E
SJIA1453J
2 – Ground : Continuity should exist.
RJIA1990E
Page 442 of 3502
ATC-64
TROUBLE DIAGNOSIS
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 is returned to the unified meter and A/C amp.
RJIA1777E
Page 445 of 3502
TROUBLE DIAGNOSIS
ATC-67
C
D
E
F
G
H
I
K
L
MA
B
AT C
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
Page 454 of 3502
ATC-76
TROUBLE DIAGNOSIS
5. CHECK GROUND CIRCUIT FOR FAN CONTROL AMP.
1. Turn ignition switch OFF.
2. Disconnect fan control amp. connector.
3. Check continuity between fan control amp. harness connector
M86 terminal 1 and ground.
OK or NG
OK >> GO TO 6.
NG >> Repair harness or connector.
6. CHECK FOR UNIFIED METER AND A/C AMP. OUTPUT SIGNAL
1. Reconnect fan control amp. connector.
2. Turn ignition switch ON.
3. Check voltage between fan control amp. harness connector
M86 terminal 2 and ground.
OK or NG
OK >> GO TO 9.
NG >>
If the voltage is lower than 2.5 V: GO TO 7.
If the voltage is higher than 10.5 V: GO TO 8.
7. CHECK CIRCUIT CONTINUITY BETWEEN UNIFIED METER AND A/C AMP. AND FAN CONTROL
AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector and fan con-
trol amp. connector.
3. Check continuity between unified meter and A/C amp. harness
connector M45 terminal 60 and fan control amp. harness con-
nector M86 terminal 2.
OK or NG
OK >> Replace fan control amp.
NG >> Repair harness or connector.1 – Ground : Continuity should exist.
RJIA2863E
Terminals
Condition Voltage (+) (−)
Fan control
amp. connectorTerminal No.
M86 2 GroundFan speed: 1st -
4th speedApprox. 2.5 -
3.5 V
Fan speed: 5th
speedApprox. 9.5 -
10.5 V
RJIA2864E
60 – 2 : Continuity should exist.
RJIA3267E
Page 457 of 3502
TROUBLE DIAGNOSIS
ATC-79
C
D
E
F
G
H
I
K
L
MA
B
AT C
SYSTEM DESCRIPTION
Unified meter and A/C amp. controls compressor operation by 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 intake
sensor.
When intake air temperature is higher than 4°C (39°F), the compres-
sor turns ON. The compressor turns OFF when intake air tempera-
ture is lower than 2.5°C (37°F).
DIAGNOSIS 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 to AT C - 4 7 , "
FUNCTION CONFIRMATION PROCEDURE" , see No. 11.
OK or NG
OK >> GO TO 2.
NG >> Malfunctioning intake sensor: Refer to ATC-105, "
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 10 A fuse (No. 79, located in IPDM E/R). Refer to PG-25, "
IPDM E/R Terminal Arrange-
ment" , and GO TO 3.
RHA094GD
PJIA0011E
Page 458 of 3502
ATC-80
TROUBLE DIAGNOSIS
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 - 4 7 , "
FUNCTION
CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-4. Confirm that magnet clutch opera-
tion normal.
NG >> 1. Replace compressor. Refer to ATC-134, "
Removal
and Installation of Compressor" .
2. Go to self-diagnosis procedure AT C - 4 7 , "
FUNCTION
CONFIRMATION PROCEDURE" and perform self-diagnosis STEP-4. Confirm that magnet
clutch operation normal.
5. CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
Check compressor ON/OFF signal. Refer to AT C - 3 4 , "
CONSULT-II
Function (BCM)" .
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
6. CHECK CIRCUIT CONTINUITY BETWEEN BCM AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect BCM connector and unified meter and A/C amp.
connector.
3. Check continuity between BCM harness connector M3 terminal
27 and unified meter and A/C amp. harness connector M45 ter-
minal 42.
OK or NG
OK >> GO TO 7.
NG >> Repair harness or connector.33 – 1 : Continuity should exist.
RJIA2004E
RJIA2005E
A/C SW ON : AIR COND SW ON
A/C SW OFF : AIR COND SW OFF
R J I A 1111 E
27 – 42 : Continuity should exist.
RJIA2006E
Page 459 of 3502
TROUBLE DIAGNOSIS
ATC-81
C
D
E
F
G
H
I
K
L
MA
B
AT C
7. CHECK VOLTAGE FOR UNIFIED METER AND A/C AMP. (COMPRESSOR ON SIGNAL)
1. Reconnect BCM connector and unified meter and A/C amp.
connector.
2. Turn ignition switch ON.
3. Check voltage between unified meter and A/C amp. harness
connector M45 terminal 42 and ground.
OK or NG
OK >> GO TO 8.
NG-1 >> If the voltage is approx. 5 V when A/C switch is ON: Replace unified meter and A/C amp.
NG-2 >> If the voltage is approx. 0 V when A/C switch is OFF: Replace BCM.
8. CHECK REFRIGERANT PRESSURE SENSOR
WITH CONSULT-II
1. Start the engine.
2. Check voltage of refrigerant pressure sensor. Refer to EC-90,
"CONSULT-II Reference Value in Data Monitor Mode" (QR
engine) or EC-434, "
CONSULT-II Reference Value in Data Mon-
itor Mode" (VQ engine).
WITHOUT CONSULT-II
1. Start the engine.
2. Check voltage between ECM harness connector F101 terminal
70 and ground.
OK or NG
OK >>WITH CONSULT-II: GO TO 9.
WITHOUT CONSULT-II: GO TO 10.
NG >> Refer to EC-339, "
REFRIGERANT PRESSURE SENSOR" (QR engine) or EC-748, "REFRIGER-
ANT PRESSURE SENSOR" (VQ engine).
Te r m i n a l s
Condition Voltage (+)
(-) Unified meter
and A/C amp.
connectorTerminal
No.
M45 42 GroundA/C switch: ON
(Blower motor oper-
ates.)Approx. 0 V
OFF switch: ON (A/C
System: OFF)Approx. 5 V
RJIA2007E
Terminals
Condition Voltage (+)
(-)
ECM con-
nectorTerminal No.
F10169 (QR engine)
GroundA/C switch: ON
(Blower motor
operates.)Approx. 1.0 - 4.0 V
70 (VQ engine)
SJIA1723E
Page 460 of 3502
ATC-82
TROUBLE DIAGNOSIS
9. CHECK BCM INPUT (FAN ON) SIGNAL
Check FAN ON/OFF signal. Refer to AT C - 3 4 , "
CONSULT-II Function
(BCM)" .
OK or NG
OK >> GO TO 12.
NG >> GO TO 10.
10. CHECK CIRCUIT CONTINUITY BETWEEN BCM AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect BCM connector and unified meter and A/C amp.
connector.
3. Check continuity between BCM harness connector M3 terminal
28 and unified meter and A/C amp. harness connector M45 ter-
minal 57.
OK or NG
OK >> GO TO 11.
NG >> Repair harness or connector.
11 . CHECK VOLTAGE FOR UNIFIED METER AND A/C AMP. (FAN ON SIGNAL)
1. Reconnect BCM connector and unified meter and A/C amp.
connector.
2. Turn ignition switch ON.
3. Check voltage between unified meter and A/C amp. harness
connector M45 terminal 57 and ground.
OK or NG
OK >> GO TO 12.
NG-1 >> If the voltage is approx. 5 V when blower motor is ON: Replace unified meter and A/C amp.
NG-2 >> If the voltage is approx. 0 V when blower motor is OFF: Replace BCM.FAN CONTROL SW ON : FAN ON SIG ON
FAN CONTROL SW OFF : FAN ON SIG OFF
R J I A 1111 E
28 – 57 : Continuity should exist.
RJIA2009E
Terminals
Condition Voltage (+)
(-) Unified meter
and A/C amp.
connectorTerminal No.
M45 57 GroundAUTO switch: ON
(Blower motor
operates.)Approx. 0 V
OFF switch: ON
(A/C system: OFF)Approx. 5 V
RJIA2010E
