Need help finishing my cruise control install on 72 GS

hey all,

I have finished installing a factory cruise control set up on my 72 GS.

I was able to figure out all vacuum and wiring connections except for this one under the dash. It comes in from the harness connected to the cruise unit with the speedo cables on the fender well.




I can't find any factory plug on the harness it fits.

Can someone give me an idea how to wire these in? Is one a power, one ground? If there is a factory female plug.....where is it?

 

It should be the connector very close to the fuse box. I believe its the power connection. The coresponding connector that it plugs into should be taped up to the main harness.

 

on a riv its the elec fuel pump and gauge wires.

 

So both are power wires, or blue is power and brown is ground?

 

Eric . You need to look in a 72 manual. I only have a 73 and a 70 so it won't be the same.

 

Are you sure it is not the connection to the brake release switch, that disengages the cruise when the brakes are applied?

 

It is not. That one is already hooked up.

 

Heres the diagram... have a look.

 

If you have the correct cruise stop light switch it has 2 separate connections one for the brake lights the other is the cruise off and on ( I think)

 

It looks like the plug for the transducer under the hood. You should have a transducer with 3 terminals. Was the harness from the transducer intact and wrapped with tape? Maybe that's the plug to the transducer and that section of wire is reversed?

 

According to the disgram Mark posted it connects to the under dash harness that goes thru the brake light switch. It clearly show the brown and blue wire and the correct plug. It continues on to power .

It appears you don't have the wiring under the dash for the 2nd brake light switch and the indicator light in the dash. Marks diagram says the rest of the harness is only in "B,C and E " series and the "A" series plugs directly into the front of the fuse box.

 

Ok, I don't have the harness that this plugs into. I checked my 2 other spare harnesses, no dice. My guess is that the brown is power and the blue powers the light. So, I will run a fused 12v to the brown and see what happens....wish me luck.

 

Why not just make the harness you need. Pretty easy plus you would get the stop switch and indicator light. You can get those plugs in many cars at the junkyard. As for the indicator light you could use a 194 bulb and socket.

How are you going to shut it off when you supply power to it ??? Seems unsafe.

 

Why don't you follow the schematic I gave you, Eric. The dark blue comes off the other side of the light where pink provides power to the light and to the brown of your plug (power to both light and system), going through the brake light switch as the cutoff. As mentioned you could easily get plugs you need or heck use spade terminals without the molded plug but follow the diagram..... that way you have indication, safety, and functionality. Just a suggestion of course coming from a guy who makes his own plugs from donors to achieve accuracy.

Mark

 

X 2 Mark. I'm worried about the safety of shutting it down. Very easy harness to make . I made a complete harness for my 69 Electra years ago and it was a pain because one of the wires was a resistance wire so I had to find the value and insert the proper resistor in the wire. This one doesn't need it.

 

I completely agree with you both. I was not reading the schematic correctly. I am not very good at reading those things. Once you put it into words I now understand. I already have the secondary brake pedal switch and pink and brown wire plug on the car. I will use my old spare harnesses and make the connections as described. Makes perfect sense now. Thanks. So much for the help. I will report back on the final outcome.

Where on a stock installation from the factory is the "cruise light " normally located on a skylark/GS. I don't seem to have any unused indicator light. I can rig one up, but would like to utilize a stock setup if possible.

 

I believe the light is in the small panel to the right of the clock. You could really use any indicator light from Pep Boys , Advance or Auto Zone . Hell any NAPA store has them. You could mount it any where for your convienence so you don't have to drill a hole in your panel. Maybe someone on here has the cruise light panel to sell. Its worth a try. Good Luck and let us know how it works out.

 

The true cruise light indicator is in the instrument panel to the right of the gauges (rectangular spot where either a rear defrost switch or buick symbol is). They made bezels that had a green light indicator in there. I don't know if there exists a bezel with only the green lens as I have one with rear defrost and the indicator lens. I am sure it exists but imagine it's hard to find. As the others say you can really set up any kind of indication you want, where you want. If needed I would modify that bezel since it's a plate and there is framework behind it to mount a light.

good you figured it out, Eric. yeah let us know how you do!

Mark

 

Originally, there was a length of optic cable that was a friction fit in the lens of the switch/indicator panel. At the other end of the cable was a connector that attached to a socket and bulb. This kept bulb heat away from the plastic lens. In absence of an optic cable, an appropriate size LED might be a reasonable substitute.

 

Jim, you are right on the fiber optic set up, and I actually am looking for one myself. Know of one??

Mark