Weird Turn Signal LED Bulb Problem

[Blokhead]

I just got new LED bulbs for the turn, and brake light on the GT750, plus the electronic flasher. When I hit either turn signal switch all four bulbs flash like I have my hazards on. The turn signals worked properly before. Anybody run into this before?



I also picked up a Bosch H4 housing that was mentioned in this thread viewtopic.php?f=2&t=2773&hilit=Bosch+h4+bulb" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Link to the sale that's still on http://store.candlepower.com/7inchheadlamps.html" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;




I want to compare the Bosch to the CPI that I have on the bike now.

[keithwwalker]

Sounds like you have your flasher unit wired in wrong? Flasher designs have only one power supply in, and one power supply out (that third wire is the ground, that gets the electricity instead of the t/s during the cycle).

So do you have your flasher unit installed so that the power out, goes to the handlebar switch?

kww

[diamondj]

I seem to recall reading that in older turn signal circuits, a resistor is needed on each blinker bulb when you switch over to LED bulbs.

http://www.customdynamics.com/led_motor ... g_faqs.htm

Jim

[jabcb]

This occurs because of how the turn signal indicator bulb is wired up. Wiring for the indicator bulb connects to the two front turn signals. See wiring diagrams: viewtopic.php?f=29&t=4743

When you signal left:
1) current goes to the left turn signal bulbs & then to ground
2) current goes to the indicator bulb, then to the right turn signal bulbs & then to ground

With stock lighting the indicator bulb is a good bit higher resistance than the turn signal bulbs, so you see the indicator bulb flash but don't see the right turn signal bulbs flash.

With LED turn signal bulbs, the indicator bulb is lower resistance than the turn signal bulbs, so you see both the indicator bulb & right turn signal bulbs flash.

I don't expect that a Load Equalizer will solve this problem when wired up per instructions.
See: http://www.customdynamics.com/load_equa ... nstall.htm

Should work if you rewire the turn signal indicator bulb so that:
1) Load Equalizer black wire connects to turn signal indicator bulb
2) other turn signal indicator bulb wire connects to ground

[keithwwalker]

Wow, good catch jabcb!

I started thinking about the old rectifier regulators and how they have diodes in them. A diode lets current flow in one direction only, but not the opposite direction.

The next step is that I googled 'turnsignal diode' and sure enough, the cruiser market have products for this very problem!
http://www.amazon.com/Kuryakyn-D-Turn-S ... B000TK7XMY
http://www.chromeglow.com/catalog.asp?prodid=688008
$8, not bad.

kww

[Blokhead]

Keith;

I bought the wrong flasher unit. When I placed the order I didn't realize that the original was a 3-wire, and I bought a 2-wire.



Diamond;

These flashers are electronic, and are made for all, or partial LED setups.



Jabcb,

Interesting find on the diode kit, although Superbright LEDs has a 3-wire flasher with the same markings on it as my stock one. I'll just have to order it, and see if it works.


Thanks for all the replies,
Dean

[keithwwalker]

Good luck, let us know if you end up needing the diode kit for the t/s indicator as well.

[rbond]

A two wire electronic flasher should work. Others here have used one on their GT750's, I put one on my GT500. Works great, got it from Autozone for $12.00. I am however using standard bulbs still.

[Blokhead]

Update;

I picked up a 3-wire electronic flasher from Auto-Zone, and temporarily hooked it up (has spade terminals), and the same thing happened....All four blinkers go off at the same time. So, I disconnected the elec. harness from the tach (dash lights), and bingo, they work perfect! Hopefully if I replace the dash blinker light with an led it will still work.



Super bright leds also has a cheap strobe for the the rear brake light http://www.superbrightleds.com/cgi-bin/ ... c-100a.htm" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;
Anybody use one?

[jabcb]

The diode kit looks to be a better solution.

Installation instructions for diode kit: http://www.kuryakyn.com/documents/insta ... C-0703.pdf
They recommend that you cut wires and permanently install the kit.

Better yet, you can get connectors from Vintage Connections so that you can install the kit without modifying the existing wiring.
http://www.vintageconnections.com/

Stock turn signal wiring:

TurnSignalStock.jpeg

Installation of diode kit using connectors:

TurnSignalModifed.jpeg

[Blokhead]

I put an led in the dash light (flasher), and the problem is solved. Turn signals now work perfect. Part no. BA9S-A4-32-12V from super bright leds.

[Ebayru]

When I put an LED dash indicator bulb in place of the incandescent one it greatly improved the situation but the opposite side turn signal bulbs still flash, but dimly. I bought the flasher unit and bulbs from Superbright. My flasher unit was a 2 wire one. Could the 2 wire flasher be the reason that the LED dash bulb didn't completely stop the opposite side from flashing?

[rbond]

Check that ALL four turn signal housings are grounded. I had both rear housings not properly grounded and all four lights would flash whether left or right was selected.

[Ebayru]

I made a diode set up for the flash indicator and the problem was totally eliminated.

What is really interesting is how little drag there is on the electrical system with the LED turn signals and tail light. I set up a voltmeter on my 74 GT550 when I was having charging problems (It turned out to be the rotor). Before I changed to LEDs the voltage would swing between 14.5 v and 8 v when the turn signals were on. It was even lower if I was braking at the time. Now there is no perceptible movement of the meter needle when braking or with the turn signals on.