Wire from switch->Need to be off when on->Relay?

[Ewingr]

I won't waste a lot of your time explaining why, but will say that I have a Cruise Control lever (switch) that is normally closed, and I need it normally open. It has been suggested that I could wire through a relay. Can anyone tell me how to wire that?

More information:

According to Rostra (mfgr of the cruise arm), the wires from the Stalk I purchased from them is like this:

Yellow = Resume/Accel
Green = Set/Coast (They say that this is the wire that I need to change from on to off)
Brown = On/Off
Red = Brake Switch - gets 12 volts

So, with that, I am thinking I would do this:

Stalk Yellow Wire--> Resume/Accel from my PCM
Stalk Green Wire--> Relay, then from Relay to the Set/Coast on my PCM. (But I don't know which ports on the relay for which wire, and what else to run to the relay)
Stalk Red Wire-> to PCM Brake wire.

Does this make sense?

Any thoughts for me?

Thanks so much.

 

[MikeHalloran]

There are some tidbits of information still unrevealed.

It's not terribly difficult to figure out in person. From here, it's much harder to figure out, and much, much harder to explain to someone who hasn't done something similar before.

I suggest that you find a local person to help you with this, or to do it for you. The consequences of a little miscommunication can get expensive.



Mike Halloran
Pembroke Pines, FL, USA

 

[patdaly]

As Mike says, it is difficult to help you from here, except to say that to use a relay to have it normally open via. a normally closed switch would require that you wire the NC contacts of said relay and use the NC switch to hold relay on at all times you do not want speed set.

As you can see, a relay failure could be quite exciting and potentially unsafe.

 

[reidh]

Why do you want to change this to normally open?

 

[Ewingr]

I am installing a 2004 Corvette LS1 Engine in my 1956 Chevrolet. I have a 1969 Oldsmobile steering column. The electronic cruise control that comes with the electronics and PCM of the Corvette engine requires a normally open switch. The only cruise control arsm I can find that will work in that older steering column are normally closed. So I need to make this change.

 

[patprimmer]

Normally open and normally closed relays are commonly available. You can even buy them designed to be wired either way.

Regards

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