Electrical question on cornering lights

[taintedsaint]

My long term resto 68 Deville is coming along and I'm prepping for some electrical upgrades. Will be using a new Painless harness as it is not a restoration to factory. Since the old tele/tilt column is toast and being replaced I have to consider powering the cornering lights. Techs at Painless don't seem to understand a cornering light, they think I mean a corner parking light. While I'm well versed at electrical work, electronic layout of the system throws me.
Here is my thought process:
Power goes up column, turn signal is activated completing circuit and power travels down column to flasher and to corresponding signal lamp. If I intercepted the power coming down the column PRIOR to flasher, so just a steady power signal, I should be able to tap it, trigger relay to activate the corresponding cornering lamp. Seems straightforward. I'm not at a point of assembly to test this theory.
Techs tell me it doesn't work that way and since I don't know how the Painless system is wired in the circuit block I have to trust they're right. Or that they don't get what I'm saying.
Any input from the electrical geniuses here?
I love the corner lights but see no other solution to the problem.

Thanks in advance.

[hornetball]

You should reference the circuit diagram in the Cadillac Service Manual and replicate that.  I have one for 1974 Cadillacs, but not sure if it is the same as 1968.

[TJ Hopland]

Without looking up how Cad originally did it to see if you could copy or re use any of that here are my thoughts....

I think you are correct where there is a feed wire going to the turn signal switch the then has a L or R output.  That output gets sent to the flasher.   So you could monitor that output to know when A turn signal is operating.   Notice I said A.  After it leaves the flasher I believe the now flashing signal gets routed back up to additional contacts on the turn signal switch where that side gets disconnected from the brake circuit and connected to the flashing circuit. 

So how did Cadillac know which side was flashing?   Guessing there were more contacts in the switch?  Maybe they were literally extra contacts for the cornering lights?   Or were they monitoring for the brake disconnect and operating a relay?

I don't have time to pull up a 70 ish drawing or even say a 80 ish to see how they did it but I can maybe think of ways I would maybe try and do it with fairly simple relays and diodes.   I will be pondering this while on a road trip today and then maybe dig into it further over the weekend if no one else comes up with ideas and the snow isn't too deep.

[cadillactim]

Cornering lamp circuit was made into turn signal switch. If you notice at the wiring connector of the switch at the base of the column their are two different half moon shaped connectors. The smaller three wire connector is the cornering lamp wires.

Tim

[Jeff Rosansky CLC #28373]

I don't know if this applies for a 68 or not.
On our 70 there is a separate connector for the cornering lights. It is in the column but it is its own separate connector. I think it gets its power from the parking light circuit, not the flasher circuit. If I have the car off  (signals dead) but the parking lights on, the cornering light will activate when I move the signal switch.
Jeff

[Jeff Rosansky CLC #28373]

Looks like Tim beat me by 30 seconds!!

[bcroe]

I think you are correct where there is a feed wire going to the turn signal switch the then has a L or R output.  That output gets sent to the flasher.   So you could monitor that output to know when A turn signal is operating.   

If the L or R signal went to the flasher, you would need 2 flashers.  Are
not, so the flasher must power the whole setup and cannot be tapped
into for L or R.  I believe you need a special turn signal switch which has
extra contacts just for cornering lights.

That said I worry this special switch could be difficult/expensive to replace. 
It occurs to me, an electronic circuit could be triggered by say the L front
light, and turn on the L cornering light, BUT have a delayed shut off so it
does not turn off during blinks.  Just use your standard column switch, or
even add cornering lights to a car.  Bruce Roe

[taintedsaint]

Well, Tim and others are right. I did go check out the old column, two connectors at bottom. Check ed diagram and sure enough, cornering lights are fed by the smaller one.
I posted in the middle of major disruption to my shop and all my manuals and diagrams were buried so I didn't go there first.

Gonna try a work around.  Thanks to all for setting me straight.