I've been driving my 72 Cutlass since about June and never noticed this. I was pulling out of the driveway and stopped to talk to the guy across the street, and he said, Did you know that when you hit your brakes, your right front parking lamp or blinker light comes on? I checked it out, and sure enough when I hit the brakes, the parking light comes on.????
I replaced the front light wiring harness and engine wiring harness with new from M&H. The trunk was still in nice shape.
Any ideas where I should start looking??
Thanks Kevin

 

Quick question-do all the rear brake lights work correctly, & light up when you hit the brakes?

 

oooooooohhh that would be the cats meow. Brake light harness to the front of the car..

It could also be a really bad ground somewhere. The 70's A bodies relied heavily on solid ground points.

 

It probably is it is a grounding issue, but it would not be the first time (by a long shot) that I've seen a "new" (meaning reproduction) wiring harness have an incorrectly wired connector. I recently solved two problems in a '67 Camaro that had "new" wiring harnesses under the hood & in the dash-two wires were swapped in the connector that goes on the back of the wiper switch, and an underhood ground had a bad crimp on a wire terminal (as in it was crimped just fine-over the insulation!). Just food for thought--

 

Thanks, I'll start with checking all the grounds. I already have ground straps from the engine to firewall, and from the body to the frame.
I "think" I also grounded the core support to the frame, but I will check that out.

 

Was the problem ever figured out on this one? My Rallye is doing the same thing... When i hit the brake both front blinker/parking lights come on, as well as the Brakes, and also my Right blinker indicator in the speedo comes on. When brake is released all turns back off. Also my Blinkers no longer work....

Any ideas on this one?

 

Bad ground in one or both of your taillights is the first thing I'd look for.

- Eric

 

I double and triple checked all my grounds and still had the problem. I found 2 other cases like this on Team Chevelle and those turned out to be the column wiring harness. Needless to say, I have had a new GM one still in the box for 2 years now. I hate wiring. I'll replace it this winter while installing the Vintage Air and have things apart.
I would check your grounds though first as mentioned. My indicator light did not come on, and my blinkers work fine.

 

How did you verify that you have good grounds? The problem with the dual filament 1157 bulbs is that if there's a ground problem in the circuit, the brake light current will flow through the parking light filaments and ground that way. The parking light filament will glow dimly when that happens. Verify that the base of the bulb is making good contact inside the socket. Often the socket spreads and loosens up or can corrode internally. KD tools sells a wire brush tool specifically for cleaning lamp sockets.

 

Hazard lights.... I had my hazard switch pushed in and that iswhy they did not work... Pulled it out and BAM everything works fine, for lights at least