bad switch vs blower motor

[jpdriver1]

hey guys --- when I turn up the speed on the blower motor, the volt guage dips to the low side. which is more likely bad switch or bad motor ?

 

1990 mj

 

thanks

[HOrnbrod]

hey guys --- when I turn up the speed on the blower motor, the volt guage dips to the low side. which is more likely bad switch or bad motor ? 1990 mj thanks

 

Could be either or most likely a partially shorted resistor pack that drops the voltage for the blower speed control. Best way to start is to disco the motor connector and temp hook it directly to the battery. If it runs well on high speed, it's most likely the resistor pack, about $24 at Rock Auto. These go bad often.

 

http://www.rockauto.com/catalog/raframecatalog.php?carcode=1180156&parttype=6557&a=FRc1180156k1140277

[jpdriver1]

great thanks --- I'll try this weekend