No numberplate illumination

Brodster

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Dont know if this is related to what Ive ben doing with the CH/LH mod but here goes.

L/H numberplate LED stopped working and as the screw had rounded off went to the Audi garage to buy 2 more holders so I could replace both together. After cutting it off the car LED bulb popped back the holder and fitted to the car.......no illumination. I then changed the R/H holder with the same LED bulb and now that doesnt work either. Ive tried turning round the bulb for polarity reasons and swapped sides but both sides no longer work.......I had a look at the side fusebox but nothing blown. Kinda stumped now. Anyone had this before.

Could it be that the 2 LED bulbs have gone????

Now going to rip my garage apart to find the bag of normal bulbs that I took out when I did the LED conversion.
 
Fuses checked......?
 
All fuses checked OK. Figured out what it is though. Managed to find the old bulbs and fitted them. Turns out that both LED bulbs had blown as there were signs of scorching around the ends of both LED's and they were exceptionally hot. Dunno what could of caused this as they have been fine up to now. Looks like I will have to get another pair from Trups. Its never ending. Car is running like a dream though so I aint complaining.
 
Hey Bud, have you tried popping the standard bulbs back in to see if they still work. Reason I ask is that I've heard that on 8P2's that once the numberplate light error has come up - ie when the bulb stops working - you need to have the fault cleared via VCDS. It might be that there is nothing wrong with the other LED that was working before, the Canbus system may have just completely shut the wiring connection down until the fault is cleared. :wub: xx

See this thread
http://www.audi-sport.net/vb/new-a3-s3-sportback-8p-chassis/113139-******-led-number-plate-bulbs-wont-work-doing-my-nut-2.html

EDIT Glad you've worked out what it is, ..strange both bulbs have gone though.
 
Hi Paullie

Yeah I cancelled out the fault and did another scan and it was still the same. Both are working now but with normal bulbs so will have to get Trups to send me another 2. I knew LED's got hot but not that hot to scorch the end of the bulb.
 
Yeah Bud, Trups will sort you out with some more no probs, for sure :wub: xx
 
LED stands for light emmiting diode a diode is essentially a non return valve for electical power
This is why they only work if installed with the correct polarity
They emit light when voltage is applied with the correct polarity
If measured with an ohmeter from + to - there will be 0 ohms but if measured between - to + it will be infinte ohms
The original 501 lamps will be so many ohms (im not sure exactly) and the more.ohms applied to the 12 volts on your car
Decreases the current (amps) your car detects
When the curent detected is diffenent to what the original bulb is the car knocks the power off to that circuit
You will need the can bus ones whuch have a resistor in to make the current the same as the standard bulb
I tried these once and my car detected a fault still but.if your turn the car off then on again it should try the circuit again
I bought the cheap ones off ebay so.no wonder they didnt work
 
Eh thanks for that Jack_tdi......but I think you've got the wrong end of the stick there but thank you anyway for informing me and everyone else on how LED's work.
 
I only explained that as when my car detected a fault it turned the power off to that circuit

I was only trying to help........... next time.i wont bother
 
I only explained that as when my car detected a fault it turned the power off to that circuit

I was only trying to help........... next time.i wont bother

Was only having a laugh with you Jack_TDI. This forum isnt all straight laced......we can have a joke sometimes. Everyones input is greatly appreciated.
 

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