Infiniti F50. Manual - part 147

TROUBLE DIAGNOSIS

ATC-113

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ATC

Sunload Sensor Circuit

EJS001YF

COMPONENT DESCRIPTION

The sunload sensor is located on the left 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 auto amplifier.

SUNLOAD INPUT PROCESS

The auto 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.

DIAGNOSTIC PROCEDURE FOR SUNLOAD SENSOR

SYMPTOM: Sunload sensor circuit is open or shorted. (25 or 

−

25) is

indicated on auto amp. as a result of conducting 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 M44
terminal 1 (SB) and ground.

OK or NG

OK

>> GO TO 2.

NG

>> GO TO 4.

RJIA0109E

RJIA0926E

1 – Ground

: Approx. 5V

RJIA0254E

ATC-114

TROUBLE DIAGNOSIS

2. 

CHECK CIRCUIT CONTINUITY BETWEEN SUNLOAD SENSOR AND AUTO AMP.

1.

Turn ignition switch OFF.

2.

Disconnect auto amp. connector.

3.

Check continuity between sunload sensor harness connector
M44 terminal 2 (R/Y) and auto amp. harness connector M119
terminal 11 (R/Y).

OK or NG

OK

>> GO TO 3.

NG

>> Repair harness or connector.

3. 

CHECK SUNLOAD SENSOR.

Refer to 

ATC-115, "Sunload Sensor"

 .

OK or NG

OK

>> 1. Replace auto amp.

2. Go to self-diagnosis 

ATC-54, "FUNCTION CONFIRMATION PROCEDURE"

  and perform self-

diagnosis STEP-2. Confirm that code No. 20 is displayed.

NG

>> 1. Replace sunload sensor.

2. Go to self-diagnosis 

ATC-54, "FUNCTION CONFIRMATION PROCEDURE"

  and perform self-

diagnosis STEP-2. Confirm that code No. 20 is displayed.

4. 

CHECK CIRCUIT CONTINUITY BETWEEN SUNLOAD SENSOR AND AUTO AMP.

1.

Turn ignition switch OFF.

2.

Disconnect auto amp. connector.

3.

Check continuity between sunload sensor harness connector
M44 terminal 1 (SB) and auto amp. harness connector M119 ter-
minal 12 (SB).

OK or NG

OK

>> 1. Replace auto amp.

2. Go to self-diagnosis 

ATC-54, "FUNCTION CONFIR-

MATION PROCEDURE"

  and perform self-diagnosis

STEP-2. Confirm that code No. 20 is displayed.

NG

>> Repair harness or connector.

2 – 11

: Continuity should exist.

RJIA0255E

1 – 12

: Continuity should exist.

RJIA0256E

TROUBLE DIAGNOSIS

ATC-115

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ATC

COMPONENT INSPECTION
Sunload Sensor

Measure voltage between auto amp. terminal 12 and ground.
If NG, replace auto amp.

●

When checking sunload sensor, select a place where sun shines directly on it.

RJIA0257E

SHA930E

ATC-116

TROUBLE DIAGNOSIS

Intake Sensor Circuit

EJS001YG

COMPONENT DESCRIPTION
Intake Sensor

The intake sensor is located on the heater & cooling unit. It converts
temperature of air after it passes through the evaporator into a resis-
tance value which is then input to the auto amp.

DIAGNOSTIC PROCEDURE FOR INTAKE SENSOR

SYMPTOM: Intake sensor circuit is open or shorted. (24 or 

−

24 is

indicated on auto amp. as a result of conducting Self-diagnosis
STEP-2.)

1. 

CHECK VOLTAGE BETWEEN INTAKE SENSOR AND GROUND

1.

Disconnect intake sensor connector.

2.

Turn ignition switch ON.

3.

Check voltage between intake sensor harness connector M90
terminal 32 (G/OR) and ground.

OK or NG

OK

>> GO TO 2.

NG

>> GO TO 4.

2. 

CHECK CIRCUIT CONTINUITY BETWEEN INTAKE SENSOR AND AUTO AMP.

1.

Turn ignition switch OFF.

2.

Disconnect auto amp. connector.

3.

Check continuity between intake sensor harness connector M90
terminal 36 (R/Y) and auto amp. harness connector M119 termi-
nal 11 (R/Y).

OK or NG

OK

>> GO TO 3.

NG

>> Repair harness or connector.

RJIA0110E

RHA056GA

32 – Ground

: Approx. 5V

RJIA0258E

36 – 11

: Continuity should exist.

RJIA0259E