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Home >> Mazda >> 1994 >> MX-5 Miata L4-1.8L DOHC >> Repair and Diagnosis >> Heating and Air Conditioning >> Evaporator Temperature Sensor / Switch >> Testing and Inspection
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Evaporator Temperature Sensor / Switch: Testing and Inspection

On-Vehicle Inspection
1. Remove the glove compartment.
2. Run the engine at idle.





3. Turn the A/C switch off and set the fan switch at 4 to operate the blower fan for a few minutes.
4. After a few minutes, turn the fan switch off and stop the engine.

Note: The thermoswitch contacts will be open if the evaporator temperature is below 0-2°C { 32-35°F }.





5. Disconnect the thermoswitch connectors and check for continuity between the switch terminals.
6. If there is no continuity, replace the thermoswitch.


Component Inspection





1. Immerse the sensing bulb in a container of ice water.
2. Check the switch operation as specified in the figure.
3. If not as specified, replace the thermoswitch.

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