Turn Signal Question

[foxfire42]

I have a 12V system. The turn signals flash normally with the engine off. When it's running the turn signals blink like they are sending Morse code, very erratic and dim. Where should I check first?

[Tom Wesenberg]

Sounds like a loose connection. If you have a fuse at the starter I'd start by bypassing it and see if it improves.

[ford31]

to start read volts at starter switch motor not running than read with motor running the problem sounds like volt problem like Tom said possible connections, alternator problem ect could also be flasher

[Hugh in NC]

Bad ground will cause unexplainable things to happen. Check everything.

Hugh

[ford31]

you are very correct,my car hauler was doing silly things,trailer brakes jumpy,lights than no lights sometimes all lights would come on dim ground at plug was bad only ground it had was ball

[jacksonchuck]

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If you have an electronic flasher, try adding a 4 ohm resistor in the ground lead pigtail that comes out of the flasher body. That fixed mine. Had LED lights all around and a Snyders electronic flasher. Went crazy when car with alternator was started and system voltage went up.

[CarlG]

Originally Posted by jacksonchuck

If you have an electronic flasher, try adding a 4 ohm resistor in the ground lead pigtail that comes out of the flasher body. That fixed mine. Had LED lights all around and a Snyders electronic flasher. Went crazy when car with alternator was started and system voltage went up.

I'll have to try that -- I had the same problem with the Electronic Flasher. Worked fine until I started the engine, then went ape. Finally just took it out and went back to the old style.

[jacksonchuck]

Now that I remember what I did, I found that a 10 ohm resister worked best but I didn't have one so I used a 4 ohm. I would guess that anything in between would work as well. The flasher operating coil or electronics don't like the high voltage. The resistor in the ground circuit reduces the voltage accross the operating coil in the flasher.

[AL in NY]

I have the same thing happening to my turn signals, but only at idle. With the engine off or running above 1000 RPMs. the electronic flasher flashes the lights normally. I have concluded, after seeing how erratic the ammeter is at idle, that the system voltage must be jumping around because the generator is barely charging. The voltage fluctuation is effecting the electronic flasher and causes it the flash the light erratically.

[BILL WILLIAMSON]

Originally Posted by jacksonchuck

Now that I remember what I did, I found that a 10 ohm resister worked best but I didn't have one so I used a 4 ohm. I would guess that anything in between would work as well. The flasher operating coil or electronics don't like the high voltage. The resistor in the ground circuit reduces the voltage accross the operating coil in the flasher.

Color code for that 10 ohm resistor is brown-black-black. I used to use them when Volvos "Ran Too Hot" Bill W.

[eagle]

A capacitor across the flasher can also help get rid of some erratics in conjunction with the resistor. If you use an electrolytic capacitor make sure the polarity is correct. Usually its not the voltage that causes the problem, but the "noisy" power. A's are NOT known for clean power! Radio Shack sells a power conditioner for CB radios that will give you a nice clean power if you wish although just for a flasher the resistor/capacitor will be all you need.