I like to think of myself as smarter than the average bear for chasing down electrical gremlins but this one has me stumped. My flasher relay suddenly started running whenever the key is on regardless of whether the turn signals or hazards are on. Weirdly, all of the lights work perfectly and as expected. Also weird is that I've done no work on anything remotely electrical so no clue what might have triggered this change. The flasher is the led compatible flasher modified per Spoke's instructions. As far as I can tell, all lights and everything electrical is working perfectly fine except for the constant annoying clicking of the relay. Luckily I can't hear it when the engine is running. Any ideas?

Is the brown wire going to the E brake grounding out where it exits.

I have the same issue, no LED, everything works fine but I can hear intermittent clicking when at idle.

The flasher will click if it sees a current drain to ground. Normally this is through the 4-way switch or turnsignal stalk. If it clicks with the turnsignal/4-ways off, then there is another electrical leak. Maybe try disconnecting the e-brake and MC switch wires to check those paths.

My personal hell. I thought I had mine licked when I found some weak contacts at a front turn signal. It went away for a few days.

Now back again and I've discovered that my reverse lights work intermittently. Going to troubleshoot those to see if that's the cause.

Please post if you solve your issue.

A dumb suggestion perhaps, but have you tried a new relay?

I'll assume your car is a '73 like mine was.

I had this same problem and it turned out to be worn door light switches which run through the the buzzer relay.

There are also two other posssibilties IIRC.

A bad MC switch....old and cooroded...or a E brake bad contact.

That circuit has serveral switched grounds with one running through the seat belt warning light.

All from memory but check the wiring diagram.

Thanks all. I've narrowed it down to the MC circuit by unplugging the two wires that connect to the brake warning light on the combo gauge, and then further isolating to determine it is the MC leg and not the parking brake leg. Now to figure out the problem because the MC, switch, and practically the whole car are new or newly refurbished with only 250 miles on the fresh resto.

Try disconnecting the MC and ebrake wires at the unit. Sounds like you're zeroing in on the issue. It could be the wires and not the switches.

Are the two wires plugged to the correct terminals? The E brake is just a switched ground wire and a simple contact switch to the frame of the car. Make sure the contact surface is really clean

Yep, they are connected correctly. Just as background, everything was working perfectly until it wasn't, nothing was done to the wiring in between working and not. Also, the complete wiring harness was refurbished, cleaning all terminals and ground connections and replacing any terminals that looked suspect. Can't rule out and internal issue in a wire, but at least I now know which wire to look at. It seems like I'm looking more for a leak to ground more than than a bad connection but will continue to do both.

For trouble shooting: First thing I did was disconnect the e-brake wire at the contact switch. No change. Then I pulled the combo gauge and pulled the pigtailed wire that connects both the e-brake wire and MC wire to the same terminal for the flashing brake light in the gauge. Relay stopped clicking. Next, I reconnected ONLY the MC wire to isolate if maybe the diode on the e-brake wire had failed, or there was some other issue in that leg and the clicking resumed without the e-brake wire connected. Can't remember if I connected the e-brake without the MC connected but it see,s pretty clear the "leak" is in the MC wire leg. I'm waiting for a belmetric order to arrive with a new lock nut for the pedal end of the accelerator cable and will do more investigation of the MC wiring while I have the pedal board out for that. This weekend I'll have the car on jack stands to change oil, readjust valves, address some small oil leaks, and hopefully hook up a new heater cable if it arrives in time. That will be a good time to pull the steering rack pan and look at the MC switch itself if needed.

Thanks for all the tips. It helped me quickly zoom in on the problem. I don't think it will be too hard to figure out from this point. It's more a matter of planning for "while I'm in there."

Got it figured out... I think. I pulled the steering rack pan off to inspect the warning light switch on the MC. The wire boot was full of water which dumped out when I pulled it off. A pretty good clue of the problem. The problem seems to be that I didn't have the right size sleeving for the two switch wires when I put the harness together and there was a crease where the sleeve folded over to allow the boot to slip on that let water run down the harness into the boot and accumulate. I've driven the car exactly one time in a very heavy rain since getting it mobile and it was shortly after that when I noticed the relay ticking.

I verified that disconnecting the wire from the switch stopped the relay clicking, but even after drying everything off with a towel, it would start clicking again (but not light the light) when I reconnected the wire. I'm assuming water seeped into the switch creating a leak to ground. I sprayed the switch with brake cleaner trying to dry it out and then warmed it up with a heat gun to further dry. Still, reconnecting the wire triggered the relay. Next I sprayed the switch with electric contact cleaner and protectant and again heated with the gun. Still clicked. After reworking the sleeving with shrink wrap and liquid electrical tape to make sure the boot was water tight, I put everything back together with the intention of ordering a new switch. To my surprise after everything was back together, no relay clicking when I turned the key on Maybe the switch finally dried out enough to stop the leak.

If I wind up having to replace the switch, where is the best place to get one? Also, does brake fluid leak out when the switch is removed? i removed the switch on my old MC and still can't tell.

Thanks for all the help on this! At least the mystery is solved, and with luck, the problem is too.