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Component Inspection





B1237 Ambient Temperature Sensor Short (Low)

Inspection/Repair - Component Inspection

Component Inspection

Check ambient sensor
1. Ignition "OFF"
2. Disconnect ambient sensor and Connect A/C control unit main harness connector.
3. Measure resistance between Signal (+) terminal of ambient sensor harness connector and Sensor ground harness connector. (Component side)

Specification : Refer the specifications in Fig.1)




Fig.1)





Fig.1) ** Specifications : Resistance value of ambient sensor as a function of temperature.
** The actual value may differ from it according to various engine condition.
4. Is "resistance" display near the specified value?





Check A/C-ECU
1. Ignition "OFF"
2. Disconnect Ambient Temp. sensor (+) and Connect A/C control unit main harness connector.
3. Ignition "ON" (ENGINE "OFF").
4. Measure voltage between Signal (+) terminal of Ambient Temp. sensor (+) harness connector and chassis ground. (Component side)

Specification : Approx. 5 V




5. Is "voltage" display near the specified value?