69 No brake lights or rear 4 way flashers

Topic states my issue. I have power to all three wires at the sequential unit. All 3 flash when the emergency switch is activated and the brake light wire is live when the pedal is depressed. Signals and tail lights work fine. Based on the troubleshooting guide, I replaced the original turn signal switch, no go. Any ideas? I also substituted a known good sequential box.


The answer is probably here below.


Have you reviewed the Turn Signal Switch Failure Diagnosis Guide on my website?

One possibility is that the brake light power feed pin on the car harness side of the turn signal switch connector is fried like the picture on page 4.

For the brake lights to work on the early original Ford sequential controllers, you need power on the green, green/orange, and orange/blue wires.


I have. Based on the guide, I replaced the turn signal switch with a new one. I have power to all three wires in the trunk controller with the flashers on and power out of and to the controller when the brake light switch is activated. I substituted a replacement controller too, to no avail. Stumped.
Would you happen to know which wire is the output to the brake lights from the sequential controller?


I can’t believe no one else has experienced this problem. I have a brand new turn signal switch and sequencer box. The turn signals and tail lights work fine. My problem is, no brake lights or rear 4-way flashers. I have opened the sequencer box and have input power with both the stop light switch or 4-way flasher activated at the proper wires. Do I have two sequential units that are defective? Thanks for any factual input.


NEED HELP! I just bought a 68 cougar 302/c4 very good shape. Had no turn or brake lights. I found the original sequencer unit and opened it all up and cleaned the contacts and the turn signals work perfect. HOWEVER… No brake lights and the hazards only blink in the middle bulbs. I of course suspected the brake light switch on the pedal. So I put a jumper in the connector and it glowed like a filament. Dead short. I unplugged everything in the trunk harness and have continuity to ground from the “non hot” side of the BL switch. If I were to run a separate wire to the trunk where could I tie it in and everything still work? Or any other suggestions that doesnt involve tearing the car apart.

Sorry I can’t help you except to say that hazard blinking in the middle only is correct.

My problem was a bad, brand new, turn signal switch from NPD. Ordered another and voila! Fixed. Thanks Vic!