3/4 blower speeds
#1
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Model: Cherokee
3/4 blower speeds
Well, the snow is going to start flying here soon. Heater blower works on 1-2-4. No 3 spd, which conveniently is the "best." Like threads for missing speeds or inadequate flow point to the blower resistor. Does this hold true here of I'm only missing one speed?
#2
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Year: 2000 Sport
Model: Cherokee
Engine: 4.0
When I had my issue it was the resistor, you could tell it was working harder on 4 but not actually pushing air out as hard as it sounded. Do you get any air on 3
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Year: 1990
Model: Cherokee
Engine: 4.0
Its the resistor, the resistor has 3 speeds, it allows a certain amount of voltage to the blower motor, the 4th speed (highest speed) is full voltage to the blower motor and doesnt go through the resistor block it goes directly to the blower motor. thats why you're only get only high speed and nothing else, its also sorta of for saftey reasons so you always have the high speed for defrosting. So yes its your resister block, your 75 perect resistor is done for.
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Put in the new resistor just now. Blower works on speed 1, increases to speed 2, speed 3 is the same as 1, and 4 is fine. No change over what I had. Now what? How do I get 3 to work properly??
#7
Old fart with a wrench
Near as I can tell, the plug on the resistor needs to be replaced. The way this works is the motor is hotwired to a full 12V and the blower switch grounds different resistor taps to create different speeds. It sounds like 1 and 3 are melted together inside the plug. Also, what causes the resistor to burn out is the blower motor drawing too many amps because of worn bearings.
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#8
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Year: 1995
Model: Cherokee(XJ)
Engine: I6 4.0L
Near as I can tell, the plug on the resistor needs to be replaced. The way this works is the motor is hotwired to a full 12V and the blower switch grounds different resistor taps to create different speeds. It sounds like 1 and 3 are melted together inside the plug. Also, what causes the resistor to burn out is the blower motor drawing too many amps because of worn bearings.
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