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Blower Motor Resistor: Testing and Inspection





Inspection

1. Ignition "ON"
2. Manually operate the control switch and measure the voltage of blower motor between pin 1 and 2.
3. Select the control switch to raise voltage until high speed.




[Specification]





*AUTO COOLING: Auto speed (4.5V~B+)
*AUTO HEATING: Auto speed (4.5V~10.5V)
4. If the measured voltage is not specification, substitute with a known-good power mosfet and check for proper operation.
5. If the problem is corrected, replace the power mosfet.