12v to 6v converter for 12V modification


I am preparing to do our first 12V vehicle modification. We have recommended specs for the 12V to 6V step down relay, but cannot seem to find one that matches to purchase. The local automotive stores think I am crazy in what I am asking for. I found one on Amazon, but the delivery date is a month out, which does not work for the project timeline. Can anyone point me in the right direction or recommend ones you have used before?!

Thanks so much!!

Hi, maybe I can help but I would need to ask a few questions first. If the car is 12v, why do you need a 6v circuit anywhere in the car? What do you have that requires the 6 volts to operate? Also, I don’t understand what a “12v to 6v step down relay” might be. I usually don’t think of a “relay” as being used to step down voltage. If you have a 12v car and need to use a relay, you would just buy a 12v relay, correct? Could you please send me the link to the Amazon item you were looking at, and perhaps that will help me understand what you are trying to do and what you need, OK?
– Doug

Hi Doug

We are doing a modification of a 12V vehicle (rather then the 6V we are proficient at), and wiring in a button switch. Another group here said we needed to use a 12v to 6v SPDT relay to drop the voltage. They used this one:


I am getting mixed information from groups and just want to be certain in what I need to do, since it is our first time modifying a 12V vehicle.

If you have recommendations or instructions for the best way to do this, please do share. I do not want to over complicate things!

Thank you!

Hi Meaghan, the relay you show should work fine. And there are a lot of others readily available that would work, too. I think all that’s going on here is a difference in language and terminology, which is why the auto parts associates are confused. I would have just called it a “12v SPDT relay” and not mentioned “6v” at all. Everything in your car will be operating off 12v, including your button switch. The relay is not “dropping” any voltage. It is just handling the motor current so the button switch will not burn out. Generally speaking (there are exceptions) you can use the same wiring circuit on a single motor 12v car as you would for a single motor 6v car. The only thing to be careful of is that all your components are both rated 12v and for the car current, which your relay is. If anything I said isn’t clear, just let me know and we can discuss it. I think you will find a 12v modification to be as easy as a 6v, as long as the child can handle the speed and acceleration of such a car. – Doug

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