KTM21 Posted July 29, 2015 Posted July 29, 2015 Just installed some LED indicators on the bike and they just stay on. I am using the flasher relay that was included with the set that I bought. I had a similar problem with my old bike and I gave up in the end. What do I have to do to get them to flash?Cheers*EDIT*Pulling the idiot bulb out lets the indicators flash but the led's stay on inbetween flashes, they're just dimmed. Quote
Whitey1984 Posted July 29, 2015 Posted July 29, 2015 Have you tried the led indicators with the original relay? if they flash but are too fast then i would say it sounds like a dodgy relay to me. Was it a decent kit or a fleabay bargain? Quote
KTM21 Posted July 29, 2015 Author Posted July 29, 2015 It was a cheap kit but they had sold 3,500 of them so I assumed they would be alright. I'll try using the original relay now. Quote
KTM21 Posted July 29, 2015 Author Posted July 29, 2015 I tried the original relay, they flashed faster but as soon as you put the idiot bulb back in, they just stay on again. Quote
Grumpy Old Git Posted July 30, 2015 Posted July 30, 2015 Deja vue.We have had a similar thread to this before. The issue is the current drain from what you call 'the idiot bulb'.If this is NOT an LED, then you need to swap it out (for a LED of the correct type).If it is an LED, then you need to increase the resistance of this circuit. Either by changing the LED to a higher restive one (lower brilliance at the same voltage) or add/increase the ballast resistor (in series with the LED). Quote
KTM21 Posted July 30, 2015 Author Posted July 30, 2015 The standard idiot bulb isn't an led but I bought a replacement led one yesterday so hopefully when that comes, it will solve the issue. Cheers Quote
Mr Fro Posted July 30, 2015 Posted July 30, 2015 Deja vue.We have had a similar thread to this before. The issue is the current drain from what you call 'the idiot bulb'.If this is NOT an LED, then you need to swap it out (for a LED of the correct type).If it is an LED, then you need to increase the resistance of this circuit. Either by changing the LED to a higher restive one (lower brilliance at the same voltage) or add/increase the ballast resistor (in series with the LED). Silly question Al: Why does the dash light have to be changed to LED - is it for preventing reverse current? If so, could a diode not be used in series instead? Quote
Grumpy Old Git Posted July 30, 2015 Posted July 30, 2015 Not a silly question Ian.It is all about the amount of current being drawn. If the 'dash' light is a standard filament type, then the resistance is quite low (in order to gain the wattage required to make it 'show' brightly). V= I x R and W = V x IWith a diode (i.e. a LED), these are low current devices (and therefore high resistance).You then need to consider the circuit. The front & rear indicators are efectively in parrallel with the 'dash' indicator and therefore if the 'dash' indicator is drawing the most current, then the front & rear will have less. This impacts on the way the flasher relay works in that it relies on he current drawn through it by the front & rear indicator to dictate the flash rate. For any other 'leccies' out there - this is a very 'dumbed down' description of the circuit.And yes, you could cure it by adding resistance in series with the bulb but, by the time you get to an acceptable flash rate, the bulb may be too dim to see in daylight. Quote
Mr Fro Posted July 30, 2015 Posted July 30, 2015 I'm with you now. You'd never guess I've got a physics A-level would you. Cheers Al! Quote
KTM21 Posted August 3, 2015 Author Posted August 3, 2015 I got the led replacement today and tried it and it works but when the indicators flash, they stay lit in-between flashes dimly. Does this matter, will it fail and mot? Quote
Grumpy Old Git Posted August 5, 2015 Posted August 5, 2015 Looking at the photo's, it would appear that not all LEDs are on (when off) and that some are overbright when on.They should all illuminate to the same level - It suggests that there is a circuit fault on the board - Strange that they are all like that. Quote
FJB4C8 Posted August 5, 2015 Posted August 5, 2015 Put one resistor on each side and all will be good Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.