The Stovebolt Site Forums The Shop Area The Electrical Bay Apply brake and can hear turn signal clicking

Hi Guys...

1965 Chevy C30 Dump Truck.

Still troubleshooting an issue with my electrical system. I am hoping this sounds familiar to someone and they can offer advice.

1. When I apply the brake pedal, the signal starts to click, but the signals on the dash do not flash. The 'GEN' light will flash instead. This occurs with or without the ignition on.

2. During troubleshooting, I removed the plug for the rear tail lights, but the problem is still occurring.

3. If I have the ignition on and turn the left signal on (still have rear tails light wire off), the signal works as expected. If I turn the right signal on, it does not click and the dash signal light stays on.

Does this sound familiar to anyone?

Thanks again...
Russ..

when you apply the brakes, the brake light switch sends power to the signal unit, which [should] send it on to the tail lights ... if the flasher is clicking [but lights not flashing], power is going to the wrong place .... I say it sounds like you have some serious shorting problems in the harness, and/or a defective signal switch, more serious troubleshooting is required

Bill

Hey Bill...

I was thinking of unpluging the signal harness going to the steering wheel and plugging in another one to test. I so hate electrical problems.

..Russ

that might help - probably need to make sure the 2nd unit is grounded to the column ... could also be something in the harness under the dash ... yes electrical can be frustrating in the extreme

Bill

Hey Bill...

I did not mention that the truck came with the 4-way hazards. I unplugged the 2 'half moon' plugs from the 4 way harness plug and noticed the purple wire (On the 4-way) was a little toasty.

I will remove the 4-way plugs from the truck's plug and plug the signal switch 'half moon' plugs directly into the truck's plug. I will test it out to see it that was the problem. If it is, it was a quick fix, except I will miss the 4-ways.

I will post back with the outcome of the test. Thank you for your help. I am hoping this is the issue.

Crazy stuff like this can be caused by a poor ground somewhere, causing current to back flow through other circuits. I left the ground cable off that was near the parking brake on a mid 70's truck one time and when you turned on the blinkers, the windshield wipers came on?! The good news is that checking grounds is fairly easy compared to finding shorts inside wiring harnesses.
Carl

One way to find a short in the harness, and yes it is a PIA. Remove the bulbs from the lights. Check from the center at the bulb socket to ground. Should be open. If you have resistance you have something wrong. With all lights off. You can then look at each socket to ground at the same time. Should show less than 1 ohm. If that is all good then turn on one circuit at a time and see if you have voltage at the center of the socket. No lights in the circuit will keep the flasher from flashing. So just a steady voltage. I hope this helps. We had a less than family approved phrase for "ground loops" at work. We all hated them. When everything else is working then go back and take a good look at those four ways. If you like them get them working to.