Blower motor resistor?

Tiny
LIONNUT
  • MEMBER
  • 2006 DODGE DAKOTA
  • V8
  • 4WD
  • AUTOMATIC
  • 36,000 MILES
My blower motor does not work. I have removed the motor and jumped it to the battery and it works fine. All the fuses checked out ok. I also checked the wiring harness plug which has power. I am assuming that the switch grounds the hot lead to the motor. Could it be the switch or a resistor that may not be functioning properly? I don't have a wiring diagram to see where the resistor would be. Would anyone know where it might be located?
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Saturday, October 11th, 2008 AT 11:58 AM

43 Replies

Tiny
JACOBANDNICKOLAS
  • MECHANIC
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Hi:
Check to see if you have power to the blower motor resistor. If you do, replace the resistor. If you don't, check the switch for power in and out. If there is power in and not out, replace the switch. Here is a guide to help you step by step with instructions in the diagrams below to show you how on your car.

https://www.2carpros.com/articles/blower-fan-motor-works-on-high-speed-only

Check out the diagrams (Below). Let us know what happens and please upload pictures or videos of the problem.
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Tuesday, October 21st, 2008 AT 1:53 PM
Tiny
LIONNUT
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I cannot find the resistor to check it. Would you know where it is? With the plug on the blower motor having power, is it a grounding circuit that runs thru the switch and resistor?
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Monday, October 27th, 2008 AT 6:55 PM
Tiny
JACOBANDNICKOLAS
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Hi Again:

If you have power to the motor, the resistor is good. If you have a digital volt meter, you could check for variations in voltage based on what speed the switch is on to make sure it's working properly. If you have power to the motor, but the motor won't run, it sounds like the motor is bad. You can remove it and run power to it to see if it runs outside of the vehicle to be sure.

Let me know what you decide.

Joe
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Monday, October 27th, 2008 AT 7:34 PM
Tiny
LIONNUT
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As I stated before, I have already checked the motor and it runs fine. I am getting full voltage at the blower motor plug regardless of the position of the switch. At the blower motor plug there is a green wire and a blue striped wire. The green wire has 12+ volts all the time. When checking with a volt meter across the 2 wires (with the plug disconnected) I get no voltage. With the plug attached to the motor, I grounded the blue striped wire and the motor ran fine. As I stated before, could this be a grounding circuit where the resistor/switch act as a variable ground? Would that mean that the resistor is somewhere between the motor and the switch on the ground side of the circuit? I still have no idea where the resistor would be located so that I could check it to see if it needs replacing.
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Wednesday, October 29th, 2008 AT 7:00 PM
Tiny
JACOBANDNICKOLAS
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Hi Again:
Yes, the resister is between the motor and the switch. I just looked it up in the manual and the resister is on the passanger side interior under the dash. It is attached to the right side of the HVAC unit. If your not geting a ground through the wiring harness and have to run a seperate ground, the resister is the problem. Keep in mind, the switch redirects the 12 volts to different areas of the resister. Thus the resister is responsible for how much power the motor gets. See if you can find it. I think that is your problem.

Joe
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Wednesday, October 29th, 2008 AT 8:13 PM
Tiny
LIONNUT
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Joe, Thanks for all of your help. I finally found the resistor, replaced it and now everything is working fine. It's the somewhat simple things in life that make you happy. Having heat again is one of those simple things. Your persistence and expertise is unparalleled and beats going to a repair station just to pay a lot of money to find a simple solution.
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Saturday, November 1st, 2008 AT 5:24 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
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Hi Again:

I'm glad you got it fixed. Take care and stay warm. If you need anything in the future, let me know.

Joe
Positive feedback is appreciated.
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Saturday, November 1st, 2008 AT 6:01 PM
Tiny
KRISK643
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  • 2 POSTS
  • 2005 DODGE DAKOTA
  • V8
  • 2WD
  • AUTOMATIC
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The blower motor resistor wiring pigtail melted onto the resistor. I purchased a repair kit for the pigtail. It was a universal repair kit and has 3 wire sets. I used the set that appeared to be the same guage wire as the original wires.
Now the blower fan blows low on the low(1)and low/med(2) setting and medium on the med/high(3) and high(4) setting.

I plan on purchasing another resistor to see if that is the problem but also would like your opinion.
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Monday, January 18th, 2021 AT 9:26 AM (Merged)
Tiny
MERLIN2021
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If the resistor melted your harnes, yes replace that too.
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Monday, January 18th, 2021 AT 9:26 AM (Merged)
Tiny
KRISK643
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I replaced the wiring and resistor because they were melted together. I am having these problems with a new resistor and wiring.
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Monday, January 18th, 2021 AT 9:26 AM (Merged)
Tiny
MERLIN2021
  • MECHANIC
  • 17,250 POSTS
OK at this point you need to have it scanned with a tool that can read the body "B" codes. The control unit may be no good.
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Monday, January 18th, 2021 AT 9:26 AM (Merged)
Tiny
STING555
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  • 2004 DODGE DAKOTA
  • V8
  • 4WD
  • AUTOMATIC
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Hi my heater fan did not work on the low setting, but worked on the high setting, then didnt work at all.
I was told it could be the heater fan resiister Do you know where it is located?
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Monday, January 18th, 2021 AT 9:26 AM (Merged)
Tiny
CARADIODOC
  • MECHANIC
  • 33,689 POSTS
Bolted to the heater box, near the fan, usually with a pair of 5/16" bolts.

This system uses an unnecessary, unreliable, complicated computer to run the system. A bad controller is more likely.

Caradiodoc
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Monday, January 18th, 2021 AT 9:26 AM (Merged)
Tiny
MIKE SENATORE
  • MEMBER
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  • 2003 DODGE DAKOTA
  • 6 CYL
  • 2WD
  • MANUAL
  • 75,000 MILES
My heater only works on high spped, I was told I needed a new resistor, I am having trouble locating the spot in the vehicle where the resistor is located
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Monday, January 18th, 2021 AT 9:26 AM (Merged)
Tiny
ARMURIERDRP
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The heater resistor card is located right under the glove box lower front left right over your left foot if you sit in the passenger seat you should see a 4 wire plugged into it. You need to remove 2 screws with a 1/4inch socket and you will have your resistor.
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Monday, January 18th, 2021 AT 9:26 AM (Merged)
Tiny
ROBINHOOD4409
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  • 2003 DODGE DAKOTA
  • 6 CYL
  • 2WD
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I cant find that little resistor coil (looks like a reastat) that is supposed to be on heater box under dash. Heater fan works on bench, relay good, fuses good, but heater fan works when it wants to.
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Monday, January 18th, 2021 AT 9:26 AM (Merged)
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 107,922 POSTS
It should be located on the heater box. Here is a picture of what you are looking for:


https://www.2carpros.com/forum/automotive_pictures/249084_2_3.jpg



Let me know if this helps.

Joe
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Monday, January 18th, 2021 AT 9:26 AM (Merged)
Tiny
DEMONTRO32
  • MEMBER
  • 4 POSTS
  • 2002 DODGE DAKOTA
  • 3.0L
  • V6
  • RWD
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I'm having a short problem in the wiring harness at the plug it's burning the plug out in already replaced the resistor and put a pig tail on to replace the burnt out plug because the first time it had looked like a wire had been pulled out somehow and it shorted but now it's done the same thing is there any way if yall have it I can get a wiring digram or yall can tell me what the dark blue wire with a yellow stripe leads to so I can figure out what is causing this. No fuses have been blown so I don't know what could be causing this.
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Monday, January 18th, 2021 AT 9:27 AM (Merged)
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 107,922 POSTS
Which resister are you referring to?
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Monday, January 18th, 2021 AT 9:27 AM (Merged)
Tiny
DEMONTRO32
  • MEMBER
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It the one inside the cab directly under the glove box area
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Monday, January 18th, 2021 AT 9:27 AM (Merged)

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