Hey Guys,

I am trying to button up my truck project, and finally drive it a bit.

I need a naturally closed brake switch. I bought a swing arm one, but it looks to be a real paint to install with making brackets, etc etc.

Has anyone here installed one, or seen a hydraulic unit that was natural closed?

Pics would be great!

Thanks!
John

 

I have a Painless Hydraulic unit in the proportioning valve (for tail lights). I am thinking I could tap this, power source as a trigger to a relay which could be constant on (closed circuit), and break circuit when brakes are applied..... hmmm

 

Pretty Sure this should work just fine.

 

I don't understand what your trying to do? Can you elaborate?

 

Sure!

I have a naturally open switch, and it closes with pressure for the brake lights, sending 12V to the lights. This is the most common switch out there, and use it for my tail lights.

However, I need a naturally closed circuit for my ECU. The computer for my 305TPI and 700R4 takes a constant 12V for the lockout function, and when brake is pressed, it will see 0V.

Buying a Natural closed switch is tough. There are some "Hotrod" swingarm ones, but they are a bit of fiddling to make work. The OEM GM ones also require more work to put in. The F1 pedal design doesn't lend well to these.

So I think the above schematic will always let 12V to the ECU, and cut it when brakes are pressed.

-John

 

Oh. I see. I would skip the second brake switch idea and use a N/C really for your ecm. Use the switched 12v brake signal after your pressure switch to open the relay to your ecm.

Sumtin like:




Not sure if that is what you meant in your schematic, I'd just use one switch for both.

 

Thats what my diagram was trying to show. I think skipping an additional switch is also the best way.

Thanks for the confirmation!