Years back while they were still making them I bought a new vintage quad gauge for my six conversion. The led warning lights have presented some issues after installation. The led gen light made the alternator not function due to its lack of resistance. Had to drop the motor and remove the alternator for that one.
The issue I'm having is the brake warning light flashes when I turn on the directionals. Has anybody else had this issue and how did you resolve it?
I realize that there aren't many of these gauges out there and who knows how many are installed. Just giving it a shot.

The original wire harness has a diode just behind the gauge to prevent exactly that.

There was a recent thread about the diode (with pictures) less than a week ago.

That be me.....and yes I am currently having problems but without the LED.

I think spoke...member name....is the current expert. The diode are there to prevent backfeed and are integral to the flasher relay and the dash lights and warning lights working correctly. Curently Ibam trouble shooting a problem with the seat belt warning light. Haven.t studied wiring diagram yet. Don.t know if this helps but the diodes play an integral part of the dash lighting setup.

Thanks for the responses. The first issue I had was when I turned on the turn signals the brake warning light flashed along with them. That turned out to be a bad flasher. It was stuck on the turn indicator side and backfeeding into the brake warning light. I replace the flasher and that solved that issue.I grabbed the original light socket and everything worked fine. Including the brake warning switch on the master cylinder. Then I hooked up the led and the brake warning lights functioned properly. Since the led is a diode I guess it serves both functions.
I found the quad gauge was wired wrong to begin. I took the hot common feed to the brake warning light. Then the ground was labeled to go the switches ( master cylinder and handbrake). This won't work. The light has to go between the two wires going to the original light. I'm going to check it again tonight. I'll get the color codes for the wires and make sure It all functions before I pass on the infor. There was no diode in my 74 car. Ill check the wiring diagram to see if it had one originally.
Dave

Ok I just double checked. If you hook up the positive lead on the brake led to the black/green/ white lead coming from the C post on the turn signal flasher. Then hook the negative lead to the brown/yellow wire from the A terminal seat belt warning really. The br/ylw wire should be the junction of 2 wires.
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