2007 INFINITI M35 component

ATC-92
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
4. CHECK UNIFIED METER AND A/C AMP. OUTPUT SIGNAL
1. Reconnect blower motor connector and unified meter and A/C
amp. connector.
2. Turn ignition switch ON.
3. Set MODE switch to VENT position.
4. Change the fan speed from Lo to Hi, and check the duty ratios
between blower motor harness connector M91 terminal 2 and
ground by using an oscilloscope. Normal terminal 2 drive signal
duty ratios are shown in the table below.
OK or NG
OK >> Replace blower motor after confirming the fan air flow does not change.
NG >> Replace unified meter and A/C amp.
COMPONENT INSPECTION
Blower Motor
Confirm smooth rotation of the blower motor.

Ensure that there are no foreign particles inside the blower unit.
RJIA4074E
RJIA4075E
RJIA4076E

TROUBLE DIAGNOSIS
ATC-97
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2007 April2007 M35/M45
8. CHECK CAN COMMUNICATION
Check CAN communication. Refer to EC-161, "
DTC U1000, U1001 CAN COMMUNICATION LINE"
(VQ35DE) or EC-865, "DTC U1000, U1001 CAN COMMUNICATION LINE" (VK45DE).

ECM – IPDM E/R

ECM – Unified meter and A/C amp.
OK or NG
OK >> Replace ECM.
NG >> Repair or replace malfunctioning part(s).
COMPONENT INSPECTION
Refrigerant Pressure Sensor
The refrigerant pressure sensor is attached to the liquid tank.
Make sure that the A/C refrigerant pressure and the sensor output
voltage are within the specified range as shown in the A/C operating
condition figure. Refer to EC-704, "
REFRIGERANT PRESSURE
SENSOR" (VQ35DE) or EC-1424, "REFRIGERANT PRESSURE
SENSOR" (VK45DE).
RJIA4080E
RJIA2954E

ATC-112
TROUBLE DIAGNOSIS
Revision: 2007 April2007 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 (0.6°F) 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

ATC-114
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
COMPONENT INSPECTION
Ambient Sensor
After disconnecting ambient sensor connector E62, measure resis-
tance between terminals 1 and 2 at sensor side. Refer to the table
below.
If NG, replace ambient sensor.
Temperature °C (°F) Resistance kΩ
−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
RJIA4091E

TROUBLE DIAGNOSIS
ATC-115
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2007 April2007 M35/M45
In-vehicle Sensor CircuitNJS000H1
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.
Aspirator
The aspirator is located on driver’s side of heater & cooling unit
assembly. It produces vacuum pressure due to air discharged from
the heater & cooling unit assembly, continuously taking compartment
air in the aspirator.
RJIA4092E
RJIA4093E
RJIA1804E

TROUBLE DIAGNOSIS
ATC-117
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2007 April2007 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 7 , "
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. Refer to 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 kΩ
−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

ATC-118
TROUBLE DIAGNOSIS
Revision: 2007 April2007 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

ATC-120
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
COMPONENT INSPECTION
Sunload Sensor
Measure voltage between unified meter and A/C amp. harness con-
nector M65 terminal 46 and ground.

When checking sunload sensor, select a place where sunshine directly on it.
If NG, replace sunload sensor.
RJIA4102E
SHA930E