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ATC-84
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Self-Diagnosis
INFOID:0000000001328194
SYMPTOM: Self-diagnosis cannot be performed.
INSPECTION FLOW
*1 ATC-125, "Removal and Installation
of Compressor Clutch"
*2ATC-125, "Removal and Installation
of Compressor Clutch"
*3AT C - 2 2 , "Maintenance of Lubricant
Quantity in Compressor"
*4AT C - 5 0 , "Operational Check"*5EM-14, "Checking Drive Belts"
(VQ35DE) or EM-170, "
Checking
Drive Belts" (VK45DE)
RJIA3108E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
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TROUBLE DIAGNOSISATC-85
< SERVICE INFORMATION >
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Memory FunctionINFOID:0000000001328195
SYMPTOM: Memory function does not operate.
INSPECTION FLOW
*1 AT C - 5 0 , "Operational Check"*2AT C - 5 2 , "Power Supply and Ground
Circuit for Auto Amp"
*3 AT C - 3 2 , "How to Perform Trouble Di-
agnosis for Quick and Accurate Re-
pair"
SJIA1803E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
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ATC-86
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Ambient Sensor Circuit
INFOID:0000000001328196
COMPONENT DESCRIPTION
Ambient Sensor
The ambient sensor is attached on the hood lock stay. It detects
ambient temperature and converts it into a resistance value which is
then input into the unified meter and A/C amp.
AMBIENT TEMPERATURE INPUT PROCESS
The unified meter and A/C amp. includes a processing circ uit for the ambient sensor input. However, when the
temperature detected by the ambient sensor increases quickly, the processing circuit retards the unified meter
and A/C amp. function. It only allows the unified mete r and A/C amp. to recognize an ambient temperature
increase of 0.33 °C (0.6 °F) per 100 seconds.
As an example, consider stopping fo r a few minutes after high speed driving. Although the actual ambient tem-
perature has not changed, the temperature detected by t he ambient sensor will increase. This is because the
heat from the engine compartment can radiate to the front grille area, location of the ambient sensor.
DIAGNOSIS PROCEDURE FOR AMBIENT SENSOR
*1AT C - 5 2 , "Power Supply and Ground
Circuit for Auto Amp"
*2AT C - 5 0 , "Operational Check"*3AT C - 4 3 , "Self-Diagnosis Function"
SJIA1595E
RJIA2016E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
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TROUBLE DIAGNOSISATC-87
< SERVICE INFORMATION >
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SYMPTOM: Ambient sensor circuit is open or shorted. (21 or −21 is
indicated on unified meter and A/C amp. as a result of performing
self-diagnosis STEP-2.)
1.CHECK VOLTAGE BETWEEN AMBIENT SENSOR AND GROUND
1. Disconnect ambient sensor connector.
2. Turn ignition switch ON.
3. Check voltage between ambient sensor harness connector E34 terminal 1 and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 4.
2.CHECK CIRCUIT CONTINUITY BETW EEN AMBIENT SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
3. Check continuity between am bient sensor harness connector
E34 terminal 2 and unified meter and A/C amp. harness connec-
tor M57 terminal 49.
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
3.CHECK AMBIENT SENSOR
Refer to "Ambient Sensor".
OK or NG
OK >> 1. Replace unified meter and A/C amp. 2. Go to self-diagnosis ATC-43, "
Self-Diagnosis Function" and perform self-diagnosis STEP-2.
Confirm that code No. 20 is displayed.
NG >> 1. Replace ambient sensor.
2. Go to self-diagnosis ATC-43, "
Self-Diagnosis Function" and perform self-diagnosis STEP-2.
Confirm that code No. 20 is displayed.
4.CHECK CIRCUIT CONTINUITY BET WEEN AMBIENT SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
RJIA1461E
1 – Ground : Approx. 5 V
RJIA2017E
2 – 49 : Continuity should exist.
RJIA2018E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
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ATC-88
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
3. Check continuity between ambient sensor harness connector
E34 terminal 1 and unified meter and A/C amp. harness connec-
tor M57 terminal 39.
4. Check continuity between am bient sensor harness connector
E34 terminal 1 and ground.
OK or NG
OK >> 1. Replace unified meter and A/C amp. 2. Go to self-diagnosis ATC-43, "
Self-Diagnosis Function" and perform self-diagnosis STEP-2.
Confirm that code No. 20 is displayed.
NG >> Repair harness or connector.
COMPONENT INSPECTION
Ambient Sensor
After disconnecting ambient sensor connector E34, measure resis-
tance between terminals 1 and 2 at sensor side. Refer to the table
below.
If NG, replace ambient sensor.
In-vehicle Sensor CircuitINFOID:0000000001328197
COMPONENT DESCRIPTION
In-vehicle Sensor
The in-vehicle sensor is located on instrument driver lower panel. It
converts variations in temperature of compartment air drawn from
the aspirator into a resistance value. It is then input into the unified
meter and A/C amp. 1 – 39 : Continuity should exist.
1 – Ground : Continuity should not exist.
RJIA2019E
Temperature
°C ( °F) Resistance k Ω
− 15 (5) 12.73
− 10 (14) 9.92
− 5 (23) 7.80
0 (32) 6.19
5 (41) 4.95
10 (50) 3.99
15 (59) 3.24
20 (68) 2.65
25 (77) 2.19
30 (86) 1.81
35 (95) 1.51
40 (104) 1.27 45 (113) 1.07
RJIA2020E
RJIA2021E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
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TROUBLE DIAGNOSISATC-89
< SERVICE INFORMATION >
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Aspirator
The aspirator is located on driver’s side of heater & cooling unit
assembly. It produces vacuum pr
essure due to air discharged from
the heater & cooling unit assembly, continuously taking compartment
air in the aspirator.
DIAGNOSIS PROCEDURE FOR IN-VEHICLE SENSOR
SYMPTOM: In-vehicle sensor circ uit is open or shorted. (22 or −22 is
indicated on unified meter and A/C amp. as a result of performing
self-diagnosis STEP-2.)
1.CHECK VOLTAGE BETWEEN IN-VEHICLE SENSOR AND GROUND
1. Disconnect in-vehicle sensor connector.
2. Turn ignition switch ON.
3. Check voltage between in-vehicle sensor harness connector M46 terminal 1 and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 4.
2.CHECK CIRCUIT CONTINUITY BETWEEN IN-VEHICLE SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
RJIA0921E
RJIA1804E
RJIA1452E
1 – Ground : Approx. 5 V
RJIA2022E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
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ATC-90
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
3. Check continuity between in-vehicle sensor harness connectorM46 terminal 2 and unified meter and A/C amp. harness con-
nector M57 terminal 49.
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
3.CHECK IN-VEHICLE SENSOR
Refer to "In-vehicle Sensor".
OK or NG
OK >> 1. Replace unified meter and A/C amp. 2. Go to self-diagnosis ATC-43, "
Self-Diagnosis Function" and perform self-diagnosis STEP-2.
Confirm that code No. 20 is displayed.
NG >> 1. Replace in-vehicle sensor.
2. Go to self-diagnosis ATC-43, "
Self-Diagnosis Function" and perform self-diagnosis STEP-2.
Confirm that code No. 20 is displayed.
4.CHECK CIRCUIT CONTINUITY BETW EEN IN-VEHICLE SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
3. Check continuity between in-vehicle sensor harness connector M46 terminal 1 and unified meter and A/C amp. harness con-
nector M57 terminal 40.
4. Check continuity between in-vehicle sensor harness connector M46 terminal 1 and ground.
OK or NG
OK >> 1. Replace unified meter and A/C amp. 2. Go to self-diagnosis ATC-43, "
Self-Diagnosis Function" and perform self-diagnosis STEP-2.
Confirm that code No. 20 is displayed.
NG >> Repair harness or connector.
COMPONENT INSPECTION
In-vehicle Sensor
2 – 49 : Continuity should exist.
RJIA2023E
1 – 40 : Continuity should exist.
1 – Ground : Continuity should not exist.
RJIA2024E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
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TROUBLE DIAGNOSISATC-91
< SERVICE INFORMATION >
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After disconnecting in-vehicle sensor connector M46, measure resis-
tance between terminals 1 and 2 at sensor side. Refer to the table
below.
If NG, replace in-vehicle sensor.
Sunload Sensor CircuitINFOID:0000000001328198
COMPONENT DESCRIPTION
Sunload Sensor
The sunload sensor is located on the passenger’s side front
defroster grille. It detects sunload entering through windshield by
means of a photo diode. The sensor converts the sunload into a cur-
rent value which is then input into the unified meter and A/C amp.
SUNLOAD INPUT PROCESS
The unified meter and A/C amp. also includes a processi ng circuit which averages the variations in detected
sunload over a period of time. This prevents drastic swings in the ATC system operation due to small or quick
variations in detected sunload.
For example, consider driving along a road bordered by an occasional group of large trees. The sunload
detected by the sunload sensor will vary whenever the tr ees obstruct the sunlight. The processing circuit aver-
ages the detected sunload over a period of time, so that the (insignificant) effect of the trees momentarily
obstructing the sunlight does not cause any change in t he ATC system operation. On the other hand, shortly
after entering a long tunnel, the system will recognize t he change in sunload, and the system will react accord-
ingly.
DIAGNOSIS PROCEDURE FOR SUNLOAD SENSOR
Temperature °C ( °F) Resistance k Ω
− 15 (5) 12.73
− 10 (14) 9.92
− 5 (23) 7.80
0 (32) 6.19
5 (41) 4.95
10 (50) 3.99
15 (59) 3.24
20 (68) 2.65
25 (77) 2.19
30 (86) 1.81
35 (95) 1.51
40 (104) 1.27 45 (113) 1.07
RJIA2025E
RJIA2026E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C