How to replace a Blower Motor Resistor

**Replacing the Wiring Harness**

When it comes to replacing the wiring harness on your vehicle, it's essential to understand the process and take the necessary precautions to avoid any mistakes. The aftermarket wiring harness has a lot of extra wire on it, which is good for those who want more options but not needed by others. In this case, we're going to push the excess wire back down to its original place to ensure a proper connection.

To start, we need to remove the connector from the old wiring harness. This can be done by carefully disconnecting the connector and pushing it back into place. Once in position, we'll check that the connector reaches no problem and secure it with a clip or tape. The kit comes supplied with four crimp-on connectors, which are used to connect each side of the wire to the middle piece. These crimp-on connectors are essential for creating a good connection.

The process of connecting the new wiring harness involves stripping the connectors on both the wiring harness and the new connector. This is done by cutting off a small amount of wire at the correct mark, then using wire strippers to strip the insulation from the exposed wire. The stripped wire is then twisted around the crimp-on connector to secure it in place. By following these steps, we can ensure that each connection is secure and reliable.

To connect the wiring harness, we need to understand the orientation of the pigtail connectors. Each connector has a specific orientation, with the green wire connected to one side, the black wire connected to another, and so on. The curled-rounded piece on the top of the connector must be facing downwards when connecting it to the wiring harness. By following this orientation, we can ensure that each connection is secure and functional.

The process of connecting the new wiring harness involves attaching the crimp-on connectors to both sides of the wire, then sliding them onto the corresponding terminals on the wiring harness. The metal part of the crimp connector is used to secure the wire in place, while the twist-and-crush technique provides a reliable connection. By testing each connection with a pull test, we can ensure that they are secure and won't come loose over time.

Once all four wires from the wiring harness have been connected, we can assemble the new wiring harness by sliding the excess wiring into its designated slot. The final step involves taping up the wiring harness to keep everything secure and tidy. By following these steps, we can ensure that our wiring harness is properly assembled and functional.

**Testing the Wiring Harness**

To test the wiring harness, we need to connect it to the blower motor resistor and check that all connections are working as expected. The red connector is used to connect the wiring harness to the blower motor resistor, while the excess wiring is tucked away in its designated slot. By checking that all attachments are secure and not rubbing against anything hot, we can ensure that the wiring harness is properly connected.

The final step involves testing the wiring harness by connecting it to the negative battery terminal and starting up the truck. The fan should turn on when the blower motor is activated, demonstrating that the wiring harness is working correctly. By testing each setting individually, we can confirm that all connections are secure and functional.

**Conclusion**

Replacing a wiring harness requires attention to detail and a thorough understanding of the process. By following these steps, we can ensure that our wiring harness is properly assembled and functional. Remember to take your time and double-check each connection to avoid any mistakes. With practice and patience, you'll be able to replace your wiring harness like a pro.

**Additional Resources**

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"WEBVTTKind: captionsLanguage: enhey guys chrisfix here today I'm going to show you how to replace a blower motor resistor if your fan doesn't work on certain speeds such as a low speed like in my case or two speeds are the same or if the only fan speed that's working is the highest speed you probably have a bad blower motor resistor so this is a blower motor resistor and what this does it looks complicated but all it does is use those coils to restrict electricity so when you have it on the lowest setting it restricts it the most so the fan doesn't blow as fast and then as you move up the higher you go up the more electricity that this resistor allows to flow through the problem is when you have it on the lowest setting you're restricting the most amount of electricity so that electricity has to go somewhere and it creates heat and this heats up a lot so a lot of times these things just fry they overheat they melt the connectors melt so that's what a blower motor resistor is and this is actually really easy to replace now these blower motor resistors are right next to the blower motor and the blower motor is commonly found either underneath the dash here on the passenger side sometimes you could open up your glove box and pull out the glove box and it'll be behind there or you go underneath and you just take out a few screws and a piece of plastic will come down and your blower motor will be right there and the other location that the blower motor could be is in the engine compartment you can see here I'm going to the passenger side of the engine compartment and this is what a blower motor looks like the blower motor is typically this round shape and then here's the actual motor and it's just a fan in there that spins around and sucks air from the outside of your car into the inside of your car so whether this blower motor is inside the vehicle or outside the vehicle in the engine compartment the blower motor resistor this thing is going to be right near it it actually uses the wind that's generated by the fan to cool it so what we're looking for is something that looks like this and on this it's actually right below here so if I lift this up you can see it right down there it has an electrical pigtail and then a bolt there and a bolt there that connects it so here are all the tools and parts you're going to need to do this job it's very simple just need a ratchet with in this case it's a eight millimeter socket I have an extension and if you're placing just a blower motor resistor that's all you're going to need but in my case I'm pretty sure you're gonna have to replace the pigtail because the pigtail looks like it's either fried or it's corroded onto the back of the current blower motor resistor so since it's like welded on it's probably shorted as well or it's just not going to come off so I'm planning on replacing it and in that case you just need a wire stripper black tape some connectors and then this came in the kit with the blower motor resistor so let's begin so as I pointed out the blower motor resistor is right next to the blower motor so what I'm gonna do is I'm gonna make it easier for me to get my hands down there I'm gonna take off this pigtail goes to the air conditioning system here all you gotta do you just pull this tab back and then slide this out and we'll just put that to the side also we could remove the blower motor cooling duct here it just provides air into the blower motor fan so it doesn't overheat just pull that out and then we could slide it down with those two things out of the way you could easily see where our blower motor resistor is and we get our hands down there really easily I'm gonna try to unclip mine but I'm pretty sure it's either welded from the corrosion or from melting plastic so here's the blower motor clip just to show you what the clip looks like there's two clips that need to be peeled backwards in order to pull this out one on the top one on the bottom this top clip should slide a little bit when I pull on this before I can lift it and it's not indicating that this is actually welded in here so what I'm gonna do now is I'm just gonna unscrew those two bolts they're eight millimeters and we're gonna take out the whole blower motor resistor with the pigtails still on it so you can see the two bolts that we need to get off I'm using an 8 millimeter with a short extension we'll get this side first okay we got one bolt out now we're gonna go in here get our other bolt out got the second bolt out and now that both bolts are out this will just come right out upon visual inspection you can see there's rust so I'm sure this is shot you could also kind of see in that hole right there it's rusty that's where the pigtail connects I'm gonna try to get the pigtail off now and see if it's really rust welded on or plastic welded on or whatever okay well I tried a couple of times I used a flathead screwdriver to really get under there and this isn't coming off so we're just gonna cut it off and since we have all those wires removed from the wiring harness this will come right out now one thing while looking at this wiring harness that I noticed right away if you look it looks like this has actually been done before somebody replaced this this is a common problem on these four words and Mazdas and also many vehicles I don't know why they can't design something better so if you still have the complete factory wiring your factory wiring is actually colored so what you want to do when you cut this you don't want to cut it right against the side of the plastic here you want to give yourself some space because then you'll be able to see which color wire goes where and you won't get the wiring mixed up so whenever you're gonna cut wires or mess around with the electrical system it's always a good idea to keep everything off keep the key out of the ignition take the negative battery terminal off before you start cutting away so now that we got our old blower motor resistor out let's get our new blower motor resistor and install it before I install it one of the biggest problems is water getting in here it's in the engine bay when I go off-roading water does get up in there even if you're just driving around in the rain water to get up in there so what I have is some dielectric grease if you want you can use a q-tip to get some grease in here so pretty much what I just did is I just coated the whole outside of the plastic so when you slide that clip in it seals it really good in my truck when we're putting this in it fits in this way it'll only fit in one way so if you have it upside down you just have to twist it and get it in the right way now I'll just get two bolts in here to hold it in place just hand tighten it for now now we'll go in here and tighten these up we'll tighten up the other side as well and you shouldn't go crazy tightening these two bolts down just make them snug good so now we got the new blower motor resistor in there if that's all you need your job is done connect the pigtail and you're good to go in my case my pigtail is melted or corroded so we need to strip these wires and put the new pigtail on I'll show you how to do that real quickly so with our wiring harness all spread apart like this I'm going to cut the aftermarket wires right at their connectors the aftermarket wiring harness has a lot of extra wire on it which is good but I don't need it at all so I'm just gonna take this kind of push it back down to place make sure the connector reaches no problem and it reaches no problem right there so I'm gonna cut off this right here good now the kit comes supplied with four of these connectors there crimp-on connectors and with these crimp-on connectors what you want to do is you want to get each side of the wire to that middle piece so you can see that little mark on my wire that's about how much you want to strip to so that you have a good connection this is 10 gauge wiring I'm gonna show you one and I'll do the rest it's all the same all you do is you get your 10 gauge on your wire cutters right here and you go to that mark you made and you close down on the wire and then you twist the wire cutter around the wire after you twist it around a couple times then you just pull the wire and then you have a stripped wire so I'm going to do the rest of these and then I'm going to strip the connectors on the wiring harness side so I got both wiring harnesses stripped and ready to go so now we'll connect them so when we're looking at the pigtail here this curled rounded piece that the clip down here is on the bottom so when we're making our connection you can see the orientation that this is in this wire here is gonna be the green wire the next wire is gonna be the black wire the top wire here is gonna be the orange wire and the bottom wire here is gonna be a yellow wire so the same thing goes for our new connector green black top is orange bottom is yellow first thing we're gonna do is put the connector on the wiring harness down here so you get your green wire and you just twist the end twisting the end is going to make it a lot easier to slide it in here so just get your crimp connector slide it all the way in the wire should go to all the way to the base of that crimp connector here the metal part of the crimp connector and when you push the wire all the way in you just get the end of your wire strippers it has like a piece here for crimping you put it on the one side and you just crimp down you test it by just pulling on it and you see that that's not coming out now we get our wire which attaches to the green wire which is this one right at the end here what's the end slide it in make sure it goes all the way in and then crimp it down test it and it's good and now we'll tape this up good so now it's nice and secure and it's nice and tidy we're going to repeat this step for all of them now all four wires from the wiring harness are connected I'm going to just put them together like this and then wrap some black tape around it make it nice and neat now we have a nice neat bundle the wiring harness is all taped up looks good let's connect it and try it out so now we'll connect the wiring harness to the blower motor resistor make sure you push it in all the way remember that we have this red connector that we disconnected up here that gets pushed in until you hear it click now we're gonna take our excess wiring harness and just tuck it in under here remember we disconnected this so just string this back around there's a hole right here that this fits into so just make sure that that is completely fit in there there's this little stub here that gets pushed in underneath here and then this opening here connects to the opening down there so all our attachments are connected we reconnected this wire here we put this blower motor cooler duct on we connected our blower motor resistor our wiring harness is tucked in and away it's not rubbing against anything not near anything hot okay let's try it out remember to connect your negative battery terminal we'll go start up the truck the moment of truth we'll put the fan on the top there we go air is coming out on the lowest setting that's awesome let's just check the other settings just to be sure air is coming out on that setting good air is even higher on that setting and then obviously the full blast work to start with but now each fan setting works properly the way it's supposed to so that's a job well done hopefully this video was helpful if it was remember to give it a thumbs up also if you're not a subscriber consider subscribing on the screen are gonna be a few how-to videos you can click on them or find the links of those videos in description below also in description below are the links to the chrisfix Facebook and Twitter pages check it outhey guys chrisfix here today I'm going to show you how to replace a blower motor resistor if your fan doesn't work on certain speeds such as a low speed like in my case or two speeds are the same or if the only fan speed that's working is the highest speed you probably have a bad blower motor resistor so this is a blower motor resistor and what this does it looks complicated but all it does is use those coils to restrict electricity so when you have it on the lowest setting it restricts it the most so the fan doesn't blow as fast and then as you move up the higher you go up the more electricity that this resistor allows to flow through the problem is when you have it on the lowest setting you're restricting the most amount of electricity so that electricity has to go somewhere and it creates heat and this heats up a lot so a lot of times these things just fry they overheat they melt the connectors melt so that's what a blower motor resistor is and this is actually really easy to replace now these blower motor resistors are right next to the blower motor and the blower motor is commonly found either underneath the dash here on the passenger side sometimes you could open up your glove box and pull out the glove box and it'll be behind there or you go underneath and you just take out a few screws and a piece of plastic will come down and your blower motor will be right there and the other location that the blower motor could be is in the engine compartment you can see here I'm going to the passenger side of the engine compartment and this is what a blower motor looks like the blower motor is typically this round shape and then here's the actual motor and it's just a fan in there that spins around and sucks air from the outside of your car into the inside of your car so whether this blower motor is inside the vehicle or outside the vehicle in the engine compartment the blower motor resistor this thing is going to be right near it it actually uses the wind that's generated by the fan to cool it so what we're looking for is something that looks like this and on this it's actually right below here so if I lift this up you can see it right down there it has an electrical pigtail and then a bolt there and a bolt there that connects it so here are all the tools and parts you're going to need to do this job it's very simple just need a ratchet with in this case it's a eight millimeter socket I have an extension and if you're placing just a blower motor resistor that's all you're going to need but in my case I'm pretty sure you're gonna have to replace the pigtail because the pigtail looks like it's either fried or it's corroded onto the back of the current blower motor resistor so since it's like welded on it's probably shorted as well or it's just not going to come off so I'm planning on replacing it and in that case you just need a wire stripper black tape some connectors and then this came in the kit with the blower motor resistor so let's begin so as I pointed out the blower motor resistor is right next to the blower motor so what I'm gonna do is I'm gonna make it easier for me to get my hands down there I'm gonna take off this pigtail goes to the air conditioning system here all you gotta do you just pull this tab back and then slide this out and we'll just put that to the side also we could remove the blower motor cooling duct here it just provides air into the blower motor fan so it doesn't overheat just pull that out and then we could slide it down with those two things out of the way you could easily see where our blower motor resistor is and we get our hands down there really easily I'm gonna try to unclip mine but I'm pretty sure it's either welded from the corrosion or from melting plastic so here's the blower motor clip just to show you what the clip looks like there's two clips that need to be peeled backwards in order to pull this out one on the top one on the bottom this top clip should slide a little bit when I pull on this before I can lift it and it's not indicating that this is actually welded in here so what I'm gonna do now is I'm just gonna unscrew those two bolts they're eight millimeters and we're gonna take out the whole blower motor resistor with the pigtails still on it so you can see the two bolts that we need to get off I'm using an 8 millimeter with a short extension we'll get this side first okay we got one bolt out now we're gonna go in here get our other bolt out got the second bolt out and now that both bolts are out this will just come right out upon visual inspection you can see there's rust so I'm sure this is shot you could also kind of see in that hole right there it's rusty that's where the pigtail connects I'm gonna try to get the pigtail off now and see if it's really rust welded on or plastic welded on or whatever okay well I tried a couple of times I used a flathead screwdriver to really get under there and this isn't coming off so we're just gonna cut it off and since we have all those wires removed from the wiring harness this will come right out now one thing while looking at this wiring harness that I noticed right away if you look it looks like this has actually been done before somebody replaced this this is a common problem on these four words and Mazdas and also many vehicles I don't know why they can't design something better so if you still have the complete factory wiring your factory wiring is actually colored so what you want to do when you cut this you don't want to cut it right against the side of the plastic here you want to give yourself some space because then you'll be able to see which color wire goes where and you won't get the wiring mixed up so whenever you're gonna cut wires or mess around with the electrical system it's always a good idea to keep everything off keep the key out of the ignition take the negative battery terminal off before you start cutting away so now that we got our old blower motor resistor out let's get our new blower motor resistor and install it before I install it one of the biggest problems is water getting in here it's in the engine bay when I go off-roading water does get up in there even if you're just driving around in the rain water to get up in there so what I have is some dielectric grease if you want you can use a q-tip to get some grease in here so pretty much what I just did is I just coated the whole outside of the plastic so when you slide that clip in it seals it really good in my truck when we're putting this in it fits in this way it'll only fit in one way so if you have it upside down you just have to twist it and get it in the right way now I'll just get two bolts in here to hold it in place just hand tighten it for now now we'll go in here and tighten these up we'll tighten up the other side as well and you shouldn't go crazy tightening these two bolts down just make them snug good so now we got the new blower motor resistor in there if that's all you need your job is done connect the pigtail and you're good to go in my case my pigtail is melted or corroded so we need to strip these wires and put the new pigtail on I'll show you how to do that real quickly so with our wiring harness all spread apart like this I'm going to cut the aftermarket wires right at their connectors the aftermarket wiring harness has a lot of extra wire on it which is good but I don't need it at all so I'm just gonna take this kind of push it back down to place make sure the connector reaches no problem and it reaches no problem right there so I'm gonna cut off this right here good now the kit comes supplied with four of these connectors there crimp-on connectors and with these crimp-on connectors what you want to do is you want to get each side of the wire to that middle piece so you can see that little mark on my wire that's about how much you want to strip to so that you have a good connection this is 10 gauge wiring I'm gonna show you one and I'll do the rest it's all the same all you do is you get your 10 gauge on your wire cutters right here and you go to that mark you made and you close down on the wire and then you twist the wire cutter around the wire after you twist it around a couple times then you just pull the wire and then you have a stripped wire so I'm going to do the rest of these and then I'm going to strip the connectors on the wiring harness side so I got both wiring harnesses stripped and ready to go so now we'll connect them so when we're looking at the pigtail here this curled rounded piece that the clip down here is on the bottom so when we're making our connection you can see the orientation that this is in this wire here is gonna be the green wire the next wire is gonna be the black wire the top wire here is gonna be the orange wire and the bottom wire here is gonna be a yellow wire so the same thing goes for our new connector green black top is orange bottom is yellow first thing we're gonna do is put the connector on the wiring harness down here so you get your green wire and you just twist the end twisting the end is going to make it a lot easier to slide it in here so just get your crimp connector slide it all the way in the wire should go to all the way to the base of that crimp connector here the metal part of the crimp connector and when you push the wire all the way in you just get the end of your wire strippers it has like a piece here for crimping you put it on the one side and you just crimp down you test it by just pulling on it and you see that that's not coming out now we get our wire which attaches to the green wire which is this one right at the end here what's the end slide it in make sure it goes all the way in and then crimp it down test it and it's good and now we'll tape this up good so now it's nice and secure and it's nice and tidy we're going to repeat this step for all of them now all four wires from the wiring harness are connected I'm going to just put them together like this and then wrap some black tape around it make it nice and neat now we have a nice neat bundle the wiring harness is all taped up looks good let's connect it and try it out so now we'll connect the wiring harness to the blower motor resistor make sure you push it in all the way remember that we have this red connector that we disconnected up here that gets pushed in until you hear it click now we're gonna take our excess wiring harness and just tuck it in under here remember we disconnected this so just string this back around there's a hole right here that this fits into so just make sure that that is completely fit in there there's this little stub here that gets pushed in underneath here and then this opening here connects to the opening down there so all our attachments are connected we reconnected this wire here we put this blower motor cooler duct on we connected our blower motor resistor our wiring harness is tucked in and away it's not rubbing against anything not near anything hot okay let's try it out remember to connect your negative battery terminal we'll go start up the truck the moment of truth we'll put the fan on the top there we go air is coming out on the lowest setting that's awesome let's just check the other settings just to be sure air is coming out on that setting good air is even higher on that setting and then obviously the full blast work to start with but now each fan setting works properly the way it's supposed to so that's a job well done hopefully this video was helpful if it was remember to give it a thumbs up also if you're not a subscriber consider subscribing on the screen are gonna be a few how-to videos you can click on them or find the links of those videos in description below also in description below are the links to the chrisfix Facebook and Twitter pages check it out\n"