Licence Plate LED: Review & Problem Solution

[fly300kts]

Hi Guys,
With all the issues with the different rear plate LED (burning, throwing codes, etc) I decided to come up with something Custom. Spent few hours on the project but between the available room, heat dispersion, available aftermarket LED, I gave up.
Browse the web to check what was available and came across these, advertising that they will not trigger any fault code, even with color display. Great, since I have a color display! They finally arrived today (they were back ordered).
Nice and bright!





Pulled the old ones, installed the LED’s, start the car and guess what, of course, Warning bulb!!! No panic, pulled them off, bring the OEM one as well, and did some testing.
At 13 volts, the OEM bulb draws 0.37 amps.




Same test performed with the LED and the draw is 0.21 amps. With such difference, there is no way that the ECU will not throw a code. Played a bit with my box of resistors and with a wirewound 50 Ohms 25 Watts, I was able to get the same value than the OEM. With this wattage, they get barely warm. Wirewound resistors are great but they are big so in order to do an acceptable work, parts have to be removed and here is the DIY.

DIY

Open the trunk; remove the fluorescent cover of the handle



Pull off the swivel the handle, and remove the 2 screws holding the upholstery panel. Pull off the handle housing




Disconnect the key barrel cable



Remove the bold (red arrow) with a 10mm wrench



Looking at the trunk from the rear, you need to turn the barrel assembly a quarter turn counter clockwise and then slide it off



Then, with the 10mm wrench, remove the two heat shields



Slide out the light assembly. Remove the 2 screws in the middle and gently separate the two parts. I was really surprised by this: with OEM bulbs, check out how the plastic is melted and cracked



Equip your resistor and solder the wires to the contacts



Close up



Clip both parts together and you should end up with something like this



Secure both resistors inside the trunk; there is plenty of room for that



Reinstall in reverse order and guess what, no code



I little tip: When you are ready to install the LED in place, turn the City Lights ON first. Then, bent upward the tabs of the light assembly and slide the light in position. Make sure they are lit before you install the PITA screw.
Contacts bent upwards



And yes, they are bright!




Let me know if any question
Phil

[ryanworth]

You use those resistors for everything. Haha. Looks good Phil. Good work as always!

[Quattro]

hahah phill, you took my lame diy and better'd it!

soon, there will be another straight solution that will not involve a resister!

[fly300kts]

hahah phill, you took my lame diy and better'd it!

soon, there will be another straight solution that will not involve a resister!

It might but I am already set

Phil

[Quattro]

phill, not everyone is an led guru like yourself :P

people like me are not on your level!

-randy

[Mc Suly]

Looks good phil as usual. you a g.

BUT thats expensive man 54.99 for a set of license plate lights.

At least you made it clear as of what to do now for the people who keep complaining.

[fly300kts]

phill, not everyone is an led guru like yourself :P

people like me are not on your level!

-randy

I just gave you all the steps to become one

Phil

[fly300kts]

Looks good phil as usual. you a g.

BUT thats expensive man 54.99 for a set of license plate lights.

At least you made it clear as of what to do now for the people who keep complaining.

It is expensive so imagine the desapointment for someone spending the $$ thinking they will no throw any code (at list for color displays). I did not want to trash my $50 so I made them work. I left them on the bench for 2 hrs and the good news is that the back housing does not get hot at all. What bother me the most is the receptacle shape, melted and cracked even with an OEM Bulb. No to bad mouth anything here but I have seen LED sold with 3 diodes and a resistor built in on the back thta will melt even more the plastic receptacle and contacts.

Bottom line, careful what you install at this location with any resistor built to the bulb itself

Phil

[kristokes]

Hey Phil, how warm did the resistors get? When I tried adding resistors to mine, it got too warm for touch so I took them off. Are yours able to be handled comfortably without the risk of 3rd degree burn lol

[fly300kts]

Hey Phil, how warm did the resistors get? When I tried adding resistors to mine, it got too warm for touch so I took them off. Are yours able to be handled comfortably without the risk of 3rd degree burn lol

Yes, after 15mn being ON, you can still hold the resistor in your hand

Phil

[cbbepop]

nice work

[Rahbey]

looks awesome man,, good work as always.

[Boushard]

Yes, after 15mn being ON, you can still hold the resistor in your hand

Phil

Where can I get resistor like that!?!?

I also had the iJDM light and I'm tired of the error message!!!

[fly300kts]

Where can I get resistor like that!?!?

I also had the iJDM light and I'm tired of the error message!!!

PM me and I will send you a pair

Phil

[Boushard]

PM me and I will send you a pair

Phil

Done

[Ais4Slow]

looks great! Im still running on stock yellow : /

[Ais4Slow]

I just installed these on my A4 and I dont have color display. But.... as soon as they came on I got an error code.

[fly300kts]

I just installed these on my A4 and I dont have color display. But.... as soon as they came on I got an error code.

Well, follow my DIY and be done with it

Phil

[Mc Suly]

I am just confused a bit about the Soldering part!!

You just have to solder the resistors to the gold part right?

PM SENT.

Are these the resistors?

RL-2525 Marker Lamp Load Resistor

* 25 Ohm, 25 Watt load resistor kit for mini wedge base bulbs
* Connect one across each LED marker light to resolve bulb-out warning indicator problems

http://www.superbrightleds.com/cgi-b...7.30406&next=0

[fly300kts]

I am just confused a bit about the Soldering part!!

You just have to solder the resistors to the gold part right?

YES
PM SENT.

PM Replied
Are these the resistors?

RL-2525 Marker Lamp Load Resistor

* 25 Ohm, 25 Watt load resistor kit for mini wedge base bulbs
* Connect one across each LED marker light to resolve bulb-out warning indicator problems

http://www.superbrightleds.com/cgi-b...7.30406&next=0

They look the same but not 100% sure

[sh0wtime]

Just a heads up;if Phil's current numbers are correct, you need a ~80 OHM resistor to get the OEM bulb current. So using a 25 OHM might not work.

[fly300kts]

Just a heads up;if Phil's current numbers are correct, you need a ~80 OHM resistor to get the OEM bulb current. So using a 25 OHM might not work.

What are you talking about?

Phil

[sh0wtime]

Just telling Mc Suly that a 25 OHM resistor might not solve the problem. There will still be a big difference in current (OEM vs the LEDs).

[fly300kts]

Just telling Mc Suly that a 25 OHM resistor might not solve the problem. There will still be a big difference in current (OEM vs the LEDs).

Do yourself a favor and read this post first

phil

[jriddle11]

Phil, I wish I lived near you because I couldn't do this on my own (even with your diy).

[thenofjboy]

^ what problem(s) did you encounter?

[fly300kts]

Phil, I wish I lived near you because I couldn't do this on my own (even with your diy).

Come on over

Phil

[Jer]

I recently replaced my left license plate bulb with a camera/LED combo becuase I wanted a backup camera. Now I get an error because the resistance is different with the single LED than the incandescent bulb that was there. Will the resistor you listed here work for any LED replacement or just the one you have specifically? Will this increase or decrease the amount of power to my LED changing the light output as well?

[Leo14]

How do you figure all of this out!? I'm going to get all these LED's than drive down to south FL and have you wire my resistors, because half of this makes no sense to me. What are the possible problems you could encounter when trying to wire resistors for LED license plate lights? Major, minor, etc? Great write up though, just wish I could use it to my advantage haha

[fly300kts]

I recently replaced my left license plate bulb with a camera/LED combo becuase I wanted a backup camera. Now I get an error because the resistance is different with the single LED than the incandescent bulb that was there. Will the resistor you listed here work for any LED replacement or just the one you have specifically? Will this increase or decrease the amount of power to my LED changing the light output as well?

If you check the fist pictures of the DIY, you will see that I am using a bench to see the exact led draw and then calculate the resistor to compensate, compared to the OEM bulb.
So I would say it will only work with my model
Nevertheless, email me a picture or send me a link of the model you bought to see if I can find some info about them, i.e draw value

Phil

[fly300kts]

How do you figure all of this out!? I'm going to get all these LED's than drive down to south FL and have you wire my resistors, because half of this makes no sense to me. What are the possible problems you could encounter when trying to wire resistors for LED license plate lights? Major, minor, etc? Great write up though, just wish I could use it to my advantage haha

Told you, come over anytime

phil

[Jer]

If you check the fist pictures of the DIY, you will see that I am using a bench to see the exact led draw and then calculate the resistor to compensate, compared to the OEM bulb.
So I would say it will only work with my model
Nevertheless, email me a picture or send me a link of the model you bought to see if I can find some info about them, i.e draw value

Phil

I can't seem to find too much in the way of specs because it was an eBay special. I had a higher end Audiovox backup camera but I opted for this one because I like the way it installed more out of sight. I did some searching and it looks like most of the people selling resistors sell 6 ohm resistors so I assume this is a universal value that should work for me as well. The camera/light combo is already installed so I don't have access to it at the moment to get some readings as far as draw goes but I have a feeling a 6 ohm resistor should do me. I need to replace the right side incandescent bulb with an LED replacement so the light output matches the LED on the left. I'm going to make sure I get one with the resistor built into it so I don't have to worry about this the next time 'round.

[lenti]

Hey Phil, i see the diy you have here, i got theese lights yesterday
http://www.ebay.de/itm/High-Power-LE...item19ca9b6130

it seems that they dont use any resistor for the canbus cuz im getting the error.. the lights works great without flickering or something, but i hate the error..
do i also need to use the 50ohm 25W resistor?
a guy who has a led shop here in sweden called, www.diodhuset.se
told me to use theese resistors and it should be okej.
http://www.diodhuset.se/1/sv/samtlig...prod_grp-s1/78
english translated
http://preview.tinyurl.com/smdled

[lenti]

Hey Phil, i see the diy you have here, i got theese lights yesterday
http://www.ebay.de/itm/High-Power-LE...item19ca9b6130

it seems that they dont use any resistor for the canbus cuz im getting the error.. the lights works great without flickering or something, but i hate the error..
do i also need to use the 50ohm 25W resistor?
a guy who has a led shop here in sweden called, www.diodhuset.se
told me to use theese resistors and it should be okej.
http://www.diodhuset.se/1/sv/samtlig...prod_grp-s1/78
english translated
http://preview.tinyurl.com/smdled

[Pared]

Just did this yesterday on a family member's car - worked magnificently.

It was exciting to work on a B7 - first mod I've tried on them. Makes me want to do more stuff to his car. :) This is certainly addicting.

Props to fly for the resistors.

[jerseybrian]

Hi Phil

I bought the bare LED bulbs from Sonic Tuning (which work, but give me the License Plate Number error) so I don't know if your DIY works for my situation. I bought (2) 50W 6Ohm resistors and after splicing one resistor inline into the power wire off the license plate bulbs harness (there is only one power wire for both the OEM bulbs), it still gave me an error. Then, I added the other resistor inline on the same power wire and the error still appeared. I'm assuming that I still don't have enough resistance? Do you think a 25W 10ohm resistor (or two) would solve the problem?

I don't have my OEM license plate bulbs anymore cuz if I knew the resistance of those bulbs, I could just measure the resistance of my LED bulbs and get the correct resistor. Does the Wattage mean much? I'm trying to figure out what equation your using to make sure everything is equal but I'm stumped. P = I^2 X R?

[jankaroni]

Hi Phil

I bought the bare LED bulbs from Sonic Tuning (which work, but give me the License Plate Number error) so I don't know if your DIY works for my situation. I bought (2) 50W 6Ohm resistors and after splicing one resistor inline into the power wire off the license plate bulbs harness (there is only one power wire for both the OEM bulbs), it still gave me an error. Then, I added the other resistor inline on the same power wire and the error still appeared. I'm assuming that I still don't have enough resistance? Do you think a 25W 10ohm resistor (or two) would solve the problem?

I don't have my OEM license plate bulbs anymore cuz if I knew the resistance of those bulbs, I could just measure the resistance of my LED bulbs and get the correct resistor. Does the Wattage mean much? I'm trying to figure out what equation your using to make sure everything is equal but I'm stumped. P = I^2 X R?

If this method isnt working for you then you could try this one... http://www.audizine.com/forum/showth...ED-Plate-light!!

I have a feeling it might just be the way that you are wiring them. Phil isn't really wiring the resistors inline he is actually wiring them in parallel with the bulbs.

[Lazze]

I found another place to put the resistor for the license plate bulbs behind the left rear panel in the trunk, now I have a avant and I do not know how it looks on a sedan. It's a gray wire in a black connector.

[waiapasi2006]

I didn't get any issues with placing led in mine at all. No bulb out warnings whatsoever, but good luck.

[PNW Avant]

Installed phil's resistors in my avant last night. Despite some absolutely hack-job solder joints, no more error! Resistors are no more than warm to the touch with the A5 LEDs after 10 min the morning. Lots of space in the avant tailgate

And to clarify, I was the one doing the soldering, had nothing to do with Phil's product, which was great!