After-market LED bulbs

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johnbreg
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After-market LED bulbs

Post by johnbreg » 29 Nov 2015, 10:12

I have tried installing LED bulbs in the rear lights of my F20 1 series. They work fine and do not show a fault indication, but due to the bulb failure check, they flash in a sequence, and this is noticeable by others. Does anyone have a way of stopping them flashing?

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M60NJP
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Re: After-market LED bulbs

Post by M60NJP » 29 Nov 2015, 10:14

Mot sure what you mean by 'flash in sequence'? Do you mean alternating left/righ/left etc? Were they canbus friendly LEDs?

johnbreg
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Re: After-market LED bulbs

Post by johnbreg » 29 Nov 2015, 10:27

Yes they are canbus friendly. The bulb failure check applies a pulse of power to every bulb in turn (sequence). With a normal bulb there is insufficient time for the element to glow, but with LED, the light is instantaneous, hence the "flash".

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M60NJP
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Re: After-market LED bulbs

Post by M60NJP » 29 Nov 2015, 10:40

Our in-house electrical expert maxwell is out this morning - he may be able to guide us later today!!

johnbreg
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Re: After-market LED bulbs

Post by johnbreg » 29 Nov 2015, 11:27

OK Thanks

Maxwell
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Re: After-market LED bulbs

Post by Maxwell » 29 Nov 2015, 17:39

Its normally only checked during the first 20 seconds or so after ignition is switched on so should not be flashing after that, canbus friendly just means it won't give a bulb out warning on the dash.
Only way to stop it completely is to code the car for LEDs

johnbreg
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Re: After-market LED bulbs

Post by johnbreg » 29 Nov 2015, 17:42

OK Thanks. I'll check again

johnbreg
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Re: After-market LED bulbs

Post by johnbreg » 29 Nov 2015, 18:19

From what I can see, it seems to send out a pulse to every light in turn - Side, Dip, Main, DTR, Fog, Rear, Brake, Indicator, Back-up, Rear Fog - total 18 lights. This happens every minute with engine running. I don't know how to code the car for LED's

johnbreg
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Re: After-market LED bulbs

Post by johnbreg » 29 Nov 2015, 18:22

I should have added that the pulses are too fast to illuminate a filament light, but with LED it is instantaneous

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