New Turn Signal Switch

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sargentrs
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Re: New Turn Signal Switch

Post by sargentrs »

Now this is irritating the crap out of me! I've spent the last hour tracing the wiring diagram trying to figure out what could be the problem. Are you sure you don't have a bad fuse? The stop lamp switch, and the hazard switch, draws it's power from a constant hot fuse. The turn signals, and the backup lights, draw their power from a different, switched hot, fuse. That's so the hazard flashers and brake lights will work with the key off while the turn signals and backup lights only work with the key on. The turn signal power comes from the accessory fuse, splices to/at the backup light switch, then goes to a connector, one wire in/2 wires out (1 to the wipers/1 to the turn signal flasher). Are your wipers working? From the turn signal flasher it goes to a 2 prong connector on the instrument cluster. This is so the turn signal indicators flash on the dash. However, the tail lights and turn signal lights are all connected to both at some point in the harness with the TSS, the flashers, the stop lamp switch and the hazard switch acting as the switches that determine where the power comes from, where it's directed to and what lights up and when. The fact that you're getting power to your bulbs when you step on the brakes and not when you flip the TSS implies that you're getting power from the hazard switch/flasher but not getting power through the TSS switch/flasher. I've read other threads where people have issues with the LED flashers and bulbs and that they solved those problems with a 12v relay in the circuit. I still think you should swap the flashers and bulbs back to the stock style and do your troubleshooting in its original configuration. I'd start with the turn signal flasher and check the connector there to make sure it's getting power on both pins with the key on and using the TSS as the on/off switch, disconnecting the stop lamp switch plug to take that power out of the circuit. With the key on, you should have power from the black wire to the turn signal flasher. With the TSS flipped, you should have power on the blue wire on the turn signal switch to the instrument cluster plug and back through the orange/yellow wire. If that's circuits working, the flasher should interrupt that signal causing the turn signal lamps to turn off and on. Is that 2 prong connector at the turn signal flasher plugged into the instrument cluster? Do your dash indicators come on too? Maybe it's a printed circuit issue on the instrument cluster?
Randy
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
QSA United
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Re: New Turn Signal Switch

Post by QSA United »

I will check into that tomorrow. I replaced the printed circuit as well when I originally purchased the turn signal switch last year. It's the same as the original, which I still have. I really appreciate the information Randy!
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bochyhawg
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Re: New Turn Signal Switch

Post by bochyhawg »

Your problem may be as simple as reversing two wires. These six wire turn signal switches are what the textbooks call a parallel circuit. When you depress the brake pedal a circuit supposed to be completed. I had to figure all this stuff out last year. There are two flashers. I takes patience to figure it out. I hope I can say something to benefit you. When you flip the emergency flasher switch 12 v is supposed to go through that flasher to all four head/tail lights as well as both arrows in the instrument panel. On the turn signal circuit juice flows differently, juice traveling through the turn signal flasher illuminates one arrow in the instrument panel and only one side of the flashers. This flow of electrons is supposed to be controlled by the turn signal switch. The last turn signal switch I installed had different colored wires. Good luck!
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