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ATC-60
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
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 3 , "
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.
4. Press the mode switch as desired.
AUXILIARY MECHANISM: INLET PORT MEMORY FUNCTION
When ignition switch is turned from OFF to ON, inlet port can be set to AUTO or manual.
Operating procedures for this trimmer are as follows:
1. Begin self-diagnosis STEP-5 mode. Refer to AT C - 5 3 , "
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.
4. Press the recirculation (REC) and fresh (FRE) switch as desired.
RJIA1971E
Switch LED status of
REC/FRE switch Setting status Setting changeover method
REC ON Manual REC status is memorized. (Initial setting)
REC SW: ON
OFF AUTO control
FRE ON Manual FRE status is memorized.
FRE SW: ON
OFF AUTO control (Initial setting)
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TROUBLE DIAGNOSIS ATC-61
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M A
B
AT C
Revision: 2005 July 2005 FX
Operational CheckAJS0014Q
The purpose of the operational check is to check if the individual system operates properly.
CHECKING MEMORY FUNCTION
1. Set the temperature to 32°C (90 °F).
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 tempera- ture.
7. Press OFF switch.
If NG, go to trouble diagnosis procedure for ATC-103, "
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 9 , "
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 - 7 0 , "
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. Conditions : Engine running at normal operating temperature
RJIA1972E
RJIA1973E
RJIA1974E
SJIA0302E
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ATC-62
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
CHECKING INTAKE AIR
1. Press recirculation (REC) switch one time. Recirculation indica-
tor should illuminate.
2. Press fresh (FRE) switch one time. Fresh indicator should illumi- nate.
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 6 , "
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 (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 1 , "
Insufficient
Cooling" .
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Press temperature (UP) switch (driver side) until 32 °C (90 °F) is
displayed.
2. Check for hot air at discharge air outlets.
If NG, go to trouble diagnosis procedure for ATC-100, "
Insufficient
Heating" .
If OK, continue the check.
CHECK 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 4 , "
Magnet Clutch
Circuit" .
If OK, continue the check.
RJIA1978E
RJIA1976E
RJIA1977E
RJIA1975E
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TROUBLE DIAGNOSIS ATC-63
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G H
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M A
B
AT C
Revision: 2005 July 2005 FX
CHECKING AUTO MODE
1. Press AUTO switch and A/C switch.
2. Display should indicate AUTO.
Confirm that the compressor clutch engages (sound or visual
inspection). (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 3 , "
Power Supply
and Ground Circuit for Auto Amp." , then if necessary, trouble diag-
nosis procedure for AT C - 8 4 , "
Magnet Clutch Circuit" .
If all operational checks are OK (symptom cannot be duplicated), go
to Incident Simulation Tests in GI-27, "
How to Perform Efficient Diag-
nosis for an Electrical Incident" and perform tests as outlined to sim-
ulate driving conditions environment. If symptom appears, refer to
AT C - 4 2 , "
SYMPTOM TABLE" and perform applicable trouble diagnosis procedures.
Power Supply and Ground Circuit for Auto Amp.AJS001BF
SYMPTOM: A/C system does not come on.
INSPECTION FLOW
RJIA1979E
*1 AT C - 6 4 , "DIAGNOSIS PROCE-
DURE FOR A/C SYSTEM"
*2ATC-61, "Operational Check"*3 AV- 7 8 , "Trouble Diagnosis Chart by
Symptom"
*4AV-166, "A/C Screen Is Not Shown
(NAVI Screen Is Shown)"
RJIA1980E
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ATC-64
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
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 switch are operated,
data is input to the unified meter and A/C amp. from the display unit/
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.
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 switch. The set temperature is dis-
played.
DIAGNOSIS PROCEDURE FOR A/C SYSTEM
SYMPTOM: A/C system does not come on.
RJIA1965E
RJIA1982E
RJIA1983E
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TROUBLE DIAGNOSIS ATC-65
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AT C
Revision: 2005 July 2005 FX
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 (R/W), 22 (G/R) and 35 (LG/R), uni-
fied meter and A/C amp. harness connector M57 terminal 46 (L/
W) and ground.
OK or NG
OK >> GO TO 2.
NG >> Check 10 A and 15 A fuses [Nos. 6, 10, 11, 12 and 19, located in the fuse block (J/B)]. Refer to
PG-82, "
FUSE BLOCK - JUNCTION BOX (J/B)" .
If fuses are OK, check harness for open circuit. Repair or replace if necessary.
If fuses are NG, replace fuse and check harness for short circuit. Repair or replace if necessary.
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 (B), 30 (B) and ground.
OK or NG
OK >> Replace unified meter and A/C amp.
NG >> Repair harness or connector.
Terminals Ignition switch position
(+)
(-) OFF ACC ON
Unified
meter and A/C amp.
connector Terminal No.
(wire color)
M56 21 (R/W)
Ground Battery volt-
age Battery volt-
age Battery
voltage
M56 22 (G/R) Approx. 0 V Approx. 0 V Battery
voltage
M56 35 (LG/R) Approx. 0 V Battery volt-
age Battery
voltage
M57 46 (L/W) Approx. 0 V Battery volt-
age Battery
voltage
RJIA1984E
29, 30 – Ground : Continuity should exist.
RJIA1985E
Page 503 of 4731
ATC-66
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
LAN System CircuitAJS0014S
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 (Y/R) and ground.
OK or NG
OK >> GO TO 2.
NG >> Replace unified meter and A/C amp.
2. CHECK SIGNAL FOR UNIFIED METER AND A/C AMP.
Confirm A/C LAN signal between unified meter and A/C amp. har-
ness connector M57 terminal 43 (G/B) and ground using an oscillo-
scope.
OK or NG
OK >> GO TO 3.
NG >> Replace unified meter and A/C amp.
RJIA1775E
54 – Ground : Battery voltage
RJIA1986E
Terminals
Voltage
(+)
( − )
Unified meter and A/
C amp. connector Terminal No.
(wire color)
M57 43 (G/B) Ground
RJIA1987E
HAK0652D
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TROUBLE DIAGNOSIS ATC-67
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D E
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G H
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K L
M A
B
AT C
Revision: 2005 July 2005 FX
3. CHECK POWER SUPPLY FOR EACH DOOR MOTOR
Check voltage between each door motor harness connector 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 terminal 2 and ground.
OK or NG
OK >> GO TO 6.
NG >> Repair harness or connector. 1 – Ground : Battery voltage
RJIA1988E
Door motor
Terminals
Voltage
(+)
( − )
Con-
nector Terminal
No.
(wire color)
Mode M258 3 (L)
Ground
Air mix
(Driver
side) M252 3 (L)
Air mix
(Passen-
ger side) M257 3 (L)
Intake M253 3 (L)
RJIA1989E
HAK0652D
2 – Ground : Continuity should exist.
RJIA1990E