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<x-charset Windows-1252>Hi Bryan, not sure why you want to do this but here goes! I had to look at my US spec wiring diag in my Haynes, as over here we just have a single filament bulb, and I think the small pilot light in the headlamp is used for the parking light- though I've never used a parking light! >From the diagram it looks like the small single filament lamp and one of the filaments of the dual bulb are used for the parking light, and the other filament (the brighter I assume?) is used for the flashers. This seems wierd as I would have thought it more beneficial if both bulbs were used for direction indicating? The indicators and hazards use the same circuit- the flasher relay is just diverted via the turn signal switch to one side or the other, or to both sides by the hazard warning switch, so you don't need to worry about that. So it looks like you've got two inputs to the assembly- one flashing and one not. I think that you should be able to make a single LED work for both functions by isolating the inputs with diodes. If you connect two diodes from the two inputs ( you can forget the single bulb holder as its wired direct to one of the connectors of the dual bulb) to the LED, it should serve both purposes. You need to connect the diodes so that their cathodes are joined together , their anodes to the connectors at the end of the bulb holder. Connect the joined cathodes to the anode of the LED via a current limiting resistor. Connect the cathode of the LED to the the chassis (the 'body' connection of the bulb holder). You will have to calculate the value of the current limiting resistor to suit the LED used: Resistor value = (Vsupply (15V) minus Vf (forward voltage of LED at desired forward current (check data sheet of LED for Vf)) minus forward voltage of diode) divided by desired forward current of LED (should be below maximum forward current for particular LED). Depending on particular LED this should probably be around 250 - 600 ohms. Bear in mind that most LEDs have quite narrow angles of view. The turn signal lens will diffuse this somewhat, but you might want to use several LEDs in each indicator. In this case you should use a current limiting resistor for each LED. The diodes should be rated to handle the combined currents flowing through the LED(s). Also check that this is legal! I know that buses are using LEDs for brake lights over here now, and many of our traffic lights are LEDs too, but I also know that its not strictly legal to rely on LED lamps on your bike- especially if they flash! Mind you we're pretty backwards in a lot of ways ;-) I hope this is of some use and not complete gobbledygook. You shouldn't need any extra relays! Good luck! Mark Seaton '73 Fastback London > It's a '73, and the assembly has one dual filament bulb, and one single > filament bulb. I'm not totally sure when the single is being used and not, > because I haven't run through all of the scenarios. The real problem comes > with the duals. I want to put in a single LED for all of it (well, one per > side). I'd like to know if anyone else has already done this, and/or what > direction I should take in this conversion. The obvious problem is going to > be flashing, and being constant on for parking lights. Then there are the > emergency flashers. I am guessing I'll have to have some relays put in to > tell it which circuit to accept behavior from, but I'm not really sure where > to start on that. > > Ideas? > > Bryan Castles > Arlington, TX > USA > '70 Bus (Ex-Westy) > '73 Square > www.version3.net > > Bryan Castles > Arlington, TX > USA > '70 Bus (Ex-Westy) > '73 Square > www.version3.net > > > ------------------------------------------------------------------- > List info at http://www.vwtype3.org/list or mailto:help@vwtype3.org > </x-charset>