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Home >> Mazda >> 1999 >> MX-5 Miata L4-1.8L DOHC >> Repair and Diagnosis >> Heating and Air Conditioning >> Control Assembly >> Testing and Inspection
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Control Assembly: Testing and Inspection

HEATER CONTROL UNIT INSPECTION

A/C Switch
1. Remove the heater control unit.







2. Inspect for continuity between the A/C switch terminals by using an ohmmeter.
3. Connect battery positive voltage to terminal C and ground to the terminal A.
4. Turn the A/C switch on.
5. Verify that the LED illuminates.
6. If not as specified, replace the A/C switch.

Fan Switch
1. Remove the heater control unit.







2. Inspect for continuity between the fan switch terminals by using an ohmmeter.
3. If not as specified, replace the fan and rear defroster switch.
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