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Blazer Complete Relay Wiring Kit with Toggle Switch

Blazer Complete Relay Wiring Kit with Toggle Switch

Item # MM510
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MM510 - Relay Wiring Kit Blazer Vehicle Lights
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This wiring kit allows your auxiliary lamps to be controlled by your vehicle's headlight circuit without overloading the circuit and blowing the fuse. Includes an illuminated power switch, 40-amp relay, fuses, and all necessary connectors. Call 800-298-1624 to order Blazer accessories and parts part number MM510 or order online at Free expert support on all Blazer products. Guaranteed Lowest Price and Fastest Shipping for Blazer Complete Relay Wiring Kit with Toggle Switch. Accessories and Parts reviews from real customers.
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Blazer Accessories and Parts - MM510

  • Vehicle Lights
  • Relay Wiring Kit
  • Blazer

This wiring kit allows your auxiliary lamps to be controlled by your vehicle's headlight circuit without overloading the circuit and blowing the fuse. Includes an illuminated power switch, 40-amp relay, fuses, and all necessary connectors.


  • Lets you wire auxiliary lights so that they function along with your vehicle lights
    • On/off toggle switch lets you manually turn lights on or off, if needed
  • Keeps your auxiliary lamps from overloading your vehicle's electrical system
    • Power circuit connects directly to battery for power
    • Control circuit draws less than 0.5 amps from the vehicle headlight system
  • Includes 40-amp relay, lighted on/off toggle switch, required fuses, and necessary connectors
  • Designed for any auxiliary device that has a high amp draw


  • Switch rating: 15 amps at 15 VDC
  • 1-Year warranty

MM510 Blazer International Complete Relay Wiring Kit

Video of Blazer Complete Relay Wiring Kit with Toggle Switch

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Blazer Complete Relay Wiring Kit with Toggle Switch Review and Installation

Hi there do it yourselfers. Today we're going to be taking a look at Blazer's complete relay wiring kit with toggle switch.If you have any powered accessories that you need to operate inside your vehicle or motor home, this will be a great way to get a switch inside your RV and have the appropriate circuits to power it properly. The most common application for this switch is to use it for lights, however my buddy Tom's dad, he uses his to operate the misters on his food truck.It's an illuminated switch that lights up when turn it on, this makes it easy to see so you know that your accessory is on. Unlike other switches this one comes with a relay. Relays are used to power a high current device using a low current switch. The switch that comes with the kit is all low current and sends the signal to the relay, energizing the relay.

The relay has heavy duty contacts on it for powering circuits that require an excessive amount of amperage.The whole circuit is fuse protected, that includes the light for the switch and whatever accessory you're going to power off the relay. You get all the wiring and everything you need to get it installed, however, you will likely need additional wiring to get your accessories wired up as the wire that comes with the kit is short.The installation is going to vary from vehicle to vehicle, and for the application you're going to be using it for. We're going to give you a general idea of how you'd hook it up to your accessory. We're going to be using ours to power some lights. We've already got our lights installed and this is the wire that will go to our lights to power them up.

After you've got your accessory installed and you've got the wires from it that you'll need to hookup to your relay, then you need to choose a location for your switch. We've decided to place ours just below the steering wheel next to our brake controller and we've cut out a small rectangle here for the switch to fit in.The switch has an outer bezel that also comes with it. That outer bezel is designed to work with curved dashes, so if you have a curved dash and you have no flat spots like we do here, you may need to use that outer bezel.The wires you see here, we're going to be using to hook to our switch. We are going to be cutting some of the ends off and using different ends for this set up. They give you a good variety of ends on the wires that come with it to work with the accessories you're using.

You do not have to use the ends however, you can choose to use whatever ends you want. If you are going to use different ends, you'll likely need some Butt Connectors.If you are replacing the ends or doing any splicing inside the vehicle you can use regular Butt Connectors, if you're doing any wiring that is outside the vehicle I recommend heat shrink Butt Connectors to keep out any moisture and prevent new corrosion from happening in the future. You can pick up but connectors here at'll begin our installation by installing our switch. There's three wires that we'll need to connect to our switch. We'll need to hook up a power wire.

We'll be using the red wire to do this because a fuse is already installed, it's a low 2 amp fuse and we want that to go to our switch to power the light on our switch as well as send our signal to our relay. We'll be hooking up the accessory, this is going to go to our relay to energize it, turning on the switch for the relay, and we'll any ground. The ground is what's going to allow the light to illuminate inside of here. We'll go ahead and start making those connections. We're going to hook our red wire up to the power circuit, they simply slide on.We're going to be using our green wire on our accessory switch as the green wire that comes in the kit has the same end of both ends, so that way it'll plug into our switch, the other end will plug into relay, and last we're going to use ground. Now, the kit does come with yellow wires for hooking up ground, but the wire that comes with it is too short to reach our ground point, so what we're going to end up doing, we are going to use the yellow wire, but we're going to cut off the end here and we're going to extend it.You can purchase some extra wire here at, or you can use some of the wire that comes in your kit that you probably won't be using. The blue wire here, we're not going to be using for our particular light setup that we're going to do. The way the blue wire would work, the white wire here that comes in your kit will connect to the output of the relay. They did this because this is a dual connector here, this is a dual ground terminal, so the blue wire can then poke in and connect to that. This way you could have another one and connect to here and you could have two different sources powered off the same wire.We're just going to be hard wiring everything, so we're not going to have these quick connects. Since we're not using our blue wire, we're going to be using our blue wire to extend our yellow wire for our ground circuit. We're going to go ahead and cut the ends off of our blue wire. We're going to strip back the yellow wire and the blue wire and we're going to connect those two together using a Butt Connector.These Butt Connectors do not come with your kit. Slide your wire in one end, crimp it, and then slide the wire on the other end in and crimp it as well.You can now feed your wires in. I'm not going to push the switch in all the way just yet, just in case I need to make any changes to it. We're just going to get it in place because once you push it in you'll have to release these ears to get it back out and that can be difficult, and we don't want to potentially damage anything trying to get it back out.We can now start hooking these wires to our relay. We're going to save the power wire until last. I always recommend you hook up your powers wires last, so that way you don't have any live circuits when you're working and it minimizes your chance of actually casing a short.Our green wire is going to go to our relay. There's a nice little diagram on top of the relay. Our switch is going to be for our energizing side, which is our 85 and 86 pins, this is the switch side, this what's going to go to whatever accessories you're powering. We're going to go ahead and find pin 85 and we're going to plug into that.Our blue wire here will connect to ground on the other end of our blue wire here we're going to be putting on a Ring Terminal. We're not going to be using the one that came with our yellow wire that we cut off because it's too small to fit on the ground stud for this vehicle. You could use that one, if you need a larger one you can pick those up here at as well.We're going to take the other end of our blue wire here, our ground stud is located back here, so we're just going to go ahead and route that wire over that direction. We're going to cut off the excess. Now, we're going to be hooking ours to the stud for our brake pedal, but depending on where you decided to mount your relay and your switch, you may not be anywhere near these components, as long as you're hooking to a ground stud or you use a self tapping screw to go into the frame or a metal component that connected to the ground on your vehicle, you'll be fine.Go on ahead and stripped back the blue wire and slid our new Ring Terminal on it, going to crimp it down. Since we're going to be hooking up this ground wire, we're going to go ahead and hook up another ground wire. This is going to be the ground for the relay. We're using the other yellow wire that comes in the kit, we did have to cut of the Ring Terminal on this one as well because it was too small. We're going to be putting on another Ring Terminal just like we did on the blue wire.We're now going to remove the nut from our ground stud, for our vehicle it's a 15 mm socket. It will likely be different for yours. We'll take our wires that we put Ring Terminals on, we're just going to bring them over, slide them on the stud, and then re-install the nut.We'll now take the wire that goes to our lights, this is the one that is coming from the accessory that you're going to be installing, again ours is lights. We're going to get that over. We're going to use the white wire that comes in the kit to make that connection. We're going to cut of this end and we're going to be Butt Connector-ing them together. We won't be needing this much wire length either, so we're going to be trimming that down.Strip back both ends, and we'll connect them together with our Butt Connector. We can now take our relay and we can start making those connections. We're going to take the ground wire that we had back here, we're going to hook that up first. This ground wire is going to go to pin 86 and we already showed you that. We hooked our switch wire to 85, we'll be hooking ground to 86. That's going to be just the opposite terminal on the back of your relay from other one.We'll then take the white wire that we connected to our accessories and we're going to connect those to pin 87 here on our relay, make that connection. Lastly, we just need to hook up our power, power is going to connect to the last terminal on our relay and also to the wire that's going up to our switch for the lights.The black wire that comes in your kit is designed to be used for power, as it's got a fuse already installed in it for the circuit. The black wire isn't long enough to reach our battery and come inside the vehicle to make this connection so we did have to extend it. We'll be using this pink wire here as that extension, the other end is going to connect to the black wire which is going to go to the battery.We're now outside the vehicle, we're going to make our connection to the battery. Our black wire has a split Ring Terminal on one end it has the connectors just like all of our other wires on the other end. Right here we cut this off so we can connect it to our pink wire to use it as an extension. We used a heat shrink Butt Connector for this connection outside, so remember to heat shrink that down using your heat gun after you've made that butt connection.Back at our battery we're going to take off the 10 mm nut here on the positive post, slide the split Ring Terminal onto it and then tighten it back down, now we can hook up our power wires. We're going to be using the rest of that black wire that we cut off out there and we're going to hook it back to the pink wire, but we're also going to be hooking up the red wire that goes to our switch there as well.We're going to strip back our pink wire and we're going to crimp on a Butt Connector. On the other end of our Butt Connector, since we need two separate power circuits, one for the relay and one for the switch, we're going to strip back a piece of the black wire we're going to be reconnecting for our relay. We're going to take our red wire, we're going to cut off some of the excess because we don't need all this for this connection.Make sure you leave your fuse inline, you don't want to cut the fuse out of the circuit. Strip that back, just going to route it over. Take the two wires, we're going to twist them together and they are both going to connect to the other side of our Butt Connector. This will give us power for both the relay and the switch.Now take the other end of the black wire and plug it into the last terminal on your relay. We can now test everything out and make sure that our accessories are working properly. We'll turn on our switch and you can see, there is the switch illuminated. Now let's checkout our lights.Now check it out, our lights are working properly and we have a professionally wired installation completed by ourselves. All that's left is to push our switch into the slot locking it in place, and then taking some zip ties to clean up our wiring. If you need some zip ties you can also pick those up here at completes our look at Blazer's complete relay wiring kit with toggle switch.

Customer Reviews

Blazer Complete Relay Wiring Kit with Toggle Switch - MM510

Average Customer Rating:  4.0 out of 5 stars   (7 Customer Reviews)

This wiring kit allows your auxiliary lamps to be controlled by your vehicle's headlight circuit without overloading the circuit and blowing the fuse. Includes an illuminated power switch, 40-amp relay, fuses, and all necessary connectors.

- MM510

When converting 4 pin to 7 pin, I used this kit as a source for trailer aux (4-pin brown) after other troubleshooting failed. A shop installed my 4 pin controller and it turns out my car doesn't supply a voltage to the quick-clipped lead for brown (and has an empty light bulb holder reserved for another model). Yes the leads in the kit are thin, but so are stock leads pumping 12v.

- MM510

Fast shipment, and product fit just wright. Excellent company. will be buying more products in the future from this awesome company.

- MM510

I ended up NOT using this for my project, the wires appears to be of low quality, surprised since everything else I have purchased from ET I've been VERY pleased with.

- MM510

Loved the lights and easy hookup,thank you

- MM510

Product received as advertised.

- MM510

- MM510


Ask the Experts about this Blazer Accessories and Parts

  • Can Blazer Complete Relay Wiring Kit be Used on Boat Center Console
    The Blazer Complete Relay Wiring Kit with Toggle Switch # MM510 is a universal type applicate, so if you wanted to you can use it on the center console of your boat. I have added a link below to a video showing the kit being installed, and while it's not on a boat it should give you a good idea of how it works.
    view full answer...
  • Is Using Relay on Blazer MM510 Wiring Kit Necessary to Wire Auxiliary Lamps on Boat
    I would recommend using the relay included with the # MM510 Blazer wiring kit, as it keeps the higher amperage from the supply to the lights from the toggle switch. If you're only running a few lamps like the # TN44RR you'd looked at, it isn't terribly important but since this is being used in a marine environment I'd recommend keeping the higher amperage away from the switch if possible, which is what the relay does for you. I've linked to an install video for the wiring kit.
    view full answer...
  • Can the MaxxTow Magnetic Tow Lights Be Hardwired Directly to a Tow Vehicle
    The MaxxTow Magnetic Tow Lights part # C6304 are designed to be placed on a towed vehicle and then powered using a four way trailer connector on a tow vehicle. The four way trailer connector on the tow vehicle is then likely ran through an integrated trailer lighting circuit which contains fuses, relays, and power from the battery. If you wanted to wire the MaxxTow Magnetic Tow Lights directly to the towed vehicle then you could use pretty much any standard automotive relay and switch...
    view full answer...
  • Can I Wire an Optronics LED Off-Road Light Bar to a 4 Way Connector?
    You could connect the Optronics LED Off-Road Light Bar # UCL23CB to a 4 way connector like the 4-Pole Trailer End Connector # 18004 in order to allow you to receive power when it is plugged into the 4 way connector on your 2019 Jeep Cherokee, but there is no running light circuit on a 4 way connector so you'd likely need to use the tail light circuit in order to accomplish this. With that being said, this really isn't going to be the best way to accomplish this. You would be much better...
    view full answer...

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Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Jacob T
Video Edited:
Jacob T
Employee Dustin K
Video by:
Dustin K
Employee Tammy D
Written by:
Tammy D
Employee Alexander C
Updated by:
Alexander C
Employee Daron K
Updated by:
Daron K
Employee David F
Installed by:
David F

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