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SUNLOAD SENSOR

SUNLOAD SENSOR

TROUBLE SYMPTOM:


• Sensor identified that sunlight is at maximum. Then, A/C system is controlled to COOL side.

• Sensor identified that sunlight is at minimum. Then, A/C system is controlled to HOT side.


Note

When the sunload sensor is checked indoors or in the shade, it may be diagnosed as open circuit. Always check the sunload sensor at a place where sun shines directly on it.


WIRING DIAGRAM:


CHECK INPUT VOLTAGE TO SUNLOAD SENSOR.

Turn the ignition switch to ON.

Measure the input voltage to sunload sensor.

Connector & terminal

(i51) No. 2 (+) — Chassis ground (−):

Is the voltage approx. 5 V?

Yes


No


CHECK HARNESS CONNECTOR BETWEEN AUTO A/C CONTROL MODULE AND SUNLOAD SENSOR.

Turn the ignition switch to OFF.

Disconnect the connectors from auto A/C control module.

Measure the resistance of harness between auto A/C control module and sunload sensor.

Connector & terminal

(i51) No. 2 — (B283) No. 16:

Is the resistance less than 1 Ω?

Yes


No

Repair the harness between auto A/C control module and sunload sensor.


CHECK HARNESS CONNECTOR BETWEEN AUTO A/C CONTROL MODULE AND SUNLOAD SENSOR.

Measure the resistance of harness between auto A/C control module and sunload sensor.

Connector & terminal

(i51) No. 1 — (B283) No. 17:

Is the resistance less than 1 Ω?

Yes


No

Repair the harness between auto A/C control module and sunload sensor.


CHECK THE INPUT VOLTAGE TO AUTO A/C CONTROL MODULE.

Connect the auto A/C control module connector.

Turn the ignition switch to ON.

Measure the voltage between auto A/C control module connector terminals.

Connector & terminal

(B283) No. 16 (+) — (B283) No. 17 (−):

Is the voltage approx. 2.5 V?

Yes


No

Replace the sunload sensor.


CHECK POOR CONTACT IN AUTO A/C CONTROL MODULE CONNECTOR.

Check poor contact in auto A/C control module connector.

Is there poor contact in connector?

Yes

Repair the connector.


No

Replace the auto A/C control module.