Page 555 of 5621

ATC-108
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
2. CHECK ECV CONTROL SIGNAL
1. Turn ignition switch OFF.
2. Reconnect compressor (ECV) connector.
3. Perform self-diagnosis. Refer to AT C - 5 5 , "
Self-diagnosis Func-
tion" .
4. Set in self-diagnosis STEP-4 (Code No. 45). Refer to AT C - 5 6 ,
"FUNCTION CONFIRMATION PROCEDURE" .
5. Confirm ECV control signal between unified meter and A/C amp.
harness connector M65 terminal 65 and ground using an oscillo-
scope.
OK or NG
OK >> Replace compressor.
NG >> GO TO 3.
3. CHECK CIRCUIT CONTINUITY BETWEEN ECV AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect compressor (ECV) and unified meter and A/C amp.
connector.
3. Check continuity between compressor (ECV) harness connector
F34 terminal 3 and unified meter and A/C amp. harness connec-
tor M65 terminal 65.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4. CHECK ECV
Check continuity between compressor (ECV) connector F34 termi-
nals 2 and 3.
OK or NG
OK >> Replace unified meter and A/C amp.
NG >> Replace compressor.
RJIA4082E
RJIA1475E
3 – 65 : Continuity should exist.
RJIA4083E
2 – 3 : Continuity should exist.
RJIA3523E
Page 558 of 5621
TROUBLE DIAGNOSIS
ATC-111
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2006 January2006 M35/M45
Self-DiagnosisNJS000GY
SYMPTOM: Self-diagnosis cannot be performed.
INSPECTION FLOW
*1AT C - 6 4 , "Operational Check"*2ATC-157, "Check Disc to Pulley
Clearance"
*3AT C - 2 6 , "Maintenance of Lubricant
Quantity in Compressor"
*4EM-15, "Checking Drive Belts"
(VQ35DE) or EM-174, "
Checking
Drive Belts" (VK45DE)
*1AT C - 6 4 , "
Operational Check"*2ATC-66, "Power Supply and Ground
Circuit for Auto Amp."
*3AT C - 4 1 , "SYMPTOM TABLE"
SJIA1699E
Page 559 of 5621
ATC-112
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
Memory FunctionNJS000GZ
SYMPTOM: Memory function does not operate.
INSPECTION FLOW
*1ATC-66, "Power Supply and Ground
Circuit for Auto Amp."
*2ATC-64, "Operational Check"*3AT C - 5 6 , "FUNCTION CONFIRMA-
TION PROCEDURE"
RJIA4086E
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TROUBLE DIAGNOSIS
ATC-113
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2006 January2006 M35/M45
Ambient Sensor CircuitNJS000H0
COMPONENT DESCRIPTION
Ambient Sensor
The ambient sensor is attached on the radiator core support (left
side). It detects ambient temperature and converts it into a resis-
tance 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 circuit 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 meter and A/C amp. to recognize an ambient temperature
increase of 0.33
C (0.6F) per 100 seconds.
As an example, consider stopping for a few minutes after high speed driving. Although the actual ambient tem-
perature has not changed, the temperature detected by the ambient sensor will increase. This is because the
heat from the engine compartment can radiate to the front bumper area, location of the ambient sensor.
DIAGNOSIS PROCEDURE FOR AMBIENT SENSOR
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 E62
terminal 1 and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 4.
RJIA4087E
RJIA4088E
1 – Ground : Approx. 5 V
RJIA2017E
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ATC-114
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
2. CHECK CIRCUIT CONTINUITY BETWEEN 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 ambient sensor harness connector
E62 terminal 2 and unified meter and A/C amp. harness connec-
tor M65 terminal 61.
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
3. CHECK AMBIENT SENSOR
Refer to AT C - 11 5 , "
Ambient Sensor" .
OK or NG
OK >> 1. Replace unified meter and A/C amp.
2. Go to self-diagnosis AT C - 5 6 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
NG >> 1. Replace ambient sensor.
2. Go to self-diagnosis AT C - 5 6 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
4. CHECK CIRCUIT CONTINUITY BETWEEN 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 ambient sensor harness connector
E62 terminal 1 and unified meter and A/C amp. harness connec-
tor M65 terminal 45.
4. Check continuity between ambient sensor harness connector
E62 terminal 1 and ground.
OK or NG
OK >> 1. Replace unified meter and A/C amp.
2. Go to self-diagnosis AT C - 5 6 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
NG >> Repair harness or connector.2 – 61 : Continuity should exist.
RJIA4089E
1 – 45 : Continuity should exist.
1 – Ground : Continuity should not exist.
RJIA4090E
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TROUBLE DIAGNOSIS
ATC-117
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2006 January2006 M35/M45
DIAGNOSIS PROCEDURE FOR IN-VEHICLE SENSOR
SYMPTOM: In-vehicle sensor circuit 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
M54 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.
3. Check continuity between in-vehicle sensor harness connector
M54 terminal 2 and unified meter and A/C amp. harness con-
nector M65 terminal 60.
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
3. CHECK IN-VEHICLE SENSOR
Refer to AT C - 11 8 , "
In-vehicle Sensor" .
OK or NG
OK >> 1. Replace unified meter and A/C amp.
2. Go to self-diagnosis AT C - 5 6 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
NG >> 1. Replace in-vehicle sensor.
2. Go to self-diagnosis AT C - 5 6 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
RJIA4094E
1 – Ground : Approx. 5 V
RJIA2022E
2 – 60 : Continuity should exist.
RJIA4095E
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ATC-118
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
4. 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.
3. Check continuity between in-vehicle sensor harness connector
M54 terminal 1 and unified meter and A/C amp. harness con-
nector M65 terminal 44.
4. Check continuity between in-vehicle sensor harness connector
M54 terminal 1 and ground.
OK or NG
OK >> 1. Replace unified meter and A/C amp.
2. Go to self-diagnosis AT C - 5 6 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
NG >> Repair harness or connector.
COMPONENT INSPECTION
In-vehicle Sensor
After disconnecting in-vehicle sensor connector M54, measure resis-
tance between terminals 1 and 2 at sensor side, using the table
below.
If NG, replace in-vehicle sensor.1 – 44 : Continuity should exist.
1 – Ground : Continuity should not exist.
RJIA4096E
Temperature C (F) Resistance k
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
RJIA4097E
Page 566 of 5621

TROUBLE DIAGNOSIS
ATC-119
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2006 January2006 M35/M45
Sunload Sensor CircuitNJS000H2
COMPONENT DESCRIPTION
Sunload Sensor
The sunload sensor is located on the driver’s side front defroster
grille. It detects sunload entering through windshield by means of a
photo diode. The sensor converts the sunload into a current 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 processing 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 trees 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 the ATC system operation. On the other hand, shortly
after entering a long tunnel, the system will recognize the change in sunload, and the system will react accord-
ingly.
DIAGNOSIS PROCEDURE FOR SUNLOAD SENSOR
SYMPTOM: Sunload sensor circuit is open or shorted. (25 or 25 is
indicated on unified meter and A/C amp. as a result of performing
self-diagnosis STEP-2.)
1. CHECK VOLTAGE BETWEEN SUNLOAD SENSOR AND GROUND
1. Disconnect sunload sensor connector.
2. Turn ignition switch ON.
3. Check voltage between sunload sensor harness connector M87
terminal 1 and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 4.
RJIA4098E
RJIA4099E
1 – Ground : Approx. 5 V
RJIA2027E