[70gp]

Originally Posted by 1965gp

I just saw this by chance, but when I went to pick up my GTO from the shop I noticed that they had a parts car that was a 69/70 GP and it had the cornering lamps in the fender. May have a harness if you need it.

This is very helpful information ! The worst part of this little project is that I don't know what I don't know, lol. I'm not sure if there's another harness under the dash that goes up to the base of the steering column that the directional switch plus into that also needs changing ? Or if it's just the turn signal switch and the headlamp harness in the engine compartment that needs changing ? I very much appreciate your help !! Thanks

[OG68]

The photos below were pulled from the '70 Service Manual. If you have a copy its in the Chassis Electric chapter (12)
Doesn't appear to be a separate harness..

[comanchefirebird]

I checked two dash harnesses I have out of 69 GP's. One is a SJ harness with cornering lights and the other a J without cornering lights. Both have a plug with three wires-brown,black and orange labeled A B C.
This is the plug that would go on the clip for the cornering lights.
First pic shows switch harness for cornering lights in the foreground and regular switch behind it. Second and third show the plug to use
Steve

[70gp]

Originally Posted by comanchefirebird

I checked two dash harnesses I have out of 69 GP's. One is a SJ harness with cornering lights and the other a J without cornering lights. Both have a plug with three wires-brown,black and orange labeled A B C.
This is the plug that would go on the clip for the cornering lights.
First pic shows switch harness for cornering lights in the foreground and regular switch behind it. Second and third show the plug to use
Steve

I am forever grateful to you for this information ! I am very happy that I don't have to goof around with changing any other harnesses under the dash. There's sure a great group of guys on here, is all I can say . Thanks again for all your efforts !!

[70gp]

Well, I ran across another hurdle over the past couple days and am posting this as an FYI to the next guy that would decide to add these cornering lights to their GP J. I made an assumption (yes, I know the saying about assume) that the '69 and '70 Grand Prix SJ's used the same headlamp harness with the cornering lamp terminals on them. I bought a used harness from a '69 SJ to use on my '70 J and when I looked closer at the harness plug that goes into the bulkhead, I noticed that one of the terminals in the plug was missing from the location it was supposed to be according to my '70 Pontiac Service Manual. Terminals used for the cornering lamp option on the '70 are in location BS & DS. The plug on the '69 harness did not even have a tab at location BS. I found a 1969 Pontiac Service Manual pdf online and found that the cornering lamp terminals were in location CT & CU on the '69 harness. A quick continuity check confirmed this, so the '69 harness is a no go. All the other connections in the plug are in a different location too. The seller was nice enough to take it back and I can get a new harness from Ames or M&H, so it's just a bump in the road. But I just am posting this to possibly save someone else the grief if they do a search on this subject.

[70gp]

Originally Posted by OG68

The photos below were pulled from the '70 Service Manual. If you have a copy its in the Chassis Electric chapter (12)
Doesn't appear to be a separate harness..

Thank you so much for your effort. I appreciate it very much !! That makes my day that I won't have to find a different harness under the dash !