Hazards on with turn signal.

[F15CrewDawg]

Howdy,
Great site, I've drawn a lot of knowledge from here and hoping some of the electrical gurus can help me gleen some more. I have a 66 F100 and I've encountered a problem with my turn signals that I can't figure out. When ever I activate a turn signal, in either direction, all four lights blink as though the hazards were on. The hazard indicator on the dash bezel stays out though. Does this with the headlights on and off and even with the hazard flasher can removed. I first noticed it while trying to put a load on my alternator after installing a new voltage regulator. I had everything in the truck turned on so I could check the battery voltage and noticed that my wipers would only move in between hazard flashes. I turned off the hazards and hit the blinker just to get something out of the front park lamps and noticed they were all still blinking and would stop blinking when I press the brakes just as if I had the hazard switch on. I would disconnect the hazard switch to see what happens but it's soldered in and not sure how to disconnect it without also cutting off my turn signals and I'm not ready to start cutting wires just yet. The only other change that's been made recently is a new headlight switch, the old one had a bad rheostat.


Thanks for any help

[BRUTUS_T_HOG]

this is typically caused by a shorted light socket.

pull out all 4 1157 bulbs one by one until you see which one causes the problem and replace it, the solder blob on the bottom of the bulb flattens out and shorts the turn signal circuit to the park light circuit.

if thats not your problem then im sure someone more familiar with your model will chime in

[F15CrewDawg]

Awesome, thanks I hadn't thought about the bulbs shorting. I'll check it out as soon as I'm off work today and post back the results.