onceyougoavant

Hello!

Working on converting my taillights, park lights, and turn markers to LED. I've successfully wired a resistor or 'load equalizer' to the turn signal circuit in the front right, however, my park light doesn't work on that corner since installing the LED bulb. I've tried wiring a resistor on that circuit in the same way as the turn signal, but it doesn't work. I tried wiring the resister in series with the LED lamp but that doesn't work either. If i put the incandescent back in everything works fine. I must be missing something. I'm going to take a nap and sleep on it, hopefully someone has some insight here.

Thanks in advance, cheers

Larhal

Have you checked the polarity of the LED light?

onceyougoavant

I'll try the LED both ways, but think I've done that already. Thank you for the suggestion!

Apparently, the LED change resistance depending on wattage so my next test will probably be to check voltage drops on the incandescent and then maybe try to re-learn ohms law to figure out if the resistance is right for the park-lights circuit.

I was doing some reading about how to calculate resistance the computer is looking for in the park light circuit here:

Resistor calculation for LED conversion in park lights

I have also been referencing this threat here, for the headlight wiring and pin-out:

B7 and B6 headlight wiring diagram

So far, a 6ohm resistor wired in parallel between Ground-8 (brn) and Signal-9 (blk-gry) works for the turn signal circuit. The park lights, who's circuit is labeled as 'LED lights' in the previous diagram (LED lights-7 (rd-gry)) do not turn on, even though VCDS registers them as 'on' in module09 Central Elec.

The voltage on LED Lights-7 varies quite a lot, with a fluctuation that can be seen in the rear taillights when i put an LED 1157 in the holder, the same rd-gry wire is for the tailitghts circuit respectively. I think this is how the electronics module determines whether or not the bulb is there by checking resistance in the circuit.

This was a lot easier in my '15 Corolla, because it didn't have error-detecting light circuits, but I'm determined to finger this out. I've got both standard LED bulbs, and CAN-bus LED bulbs enroute. I only have four (4) 6ohm resistors to play with right now, but ultimately I'm tryna get markers, park/tail, brake, and reverse in LED, hoping it doesn't take a resistor for every circuit. I'm going to try both types of LED and report back. Figure there should be a new article about this as the two I've found are many years old.

If anybody has any suggestions they are greatly appreciated,
cheers.

onceyougoavant

Update; I've gotten a few steps further, but after this post I'm about to do something else for a while. Task saturation does nobody any good.

I've gained park lights but lost the flasher, is seems there's a mutual exclusivity thing going on here, let me explain:

• When resistor is wired parallel to park lights they work but flashers do not. Hyperflash. (6ohm parallel from red-grey7 to brown8)
• When resistor is wired parallel to flashers they work but park lights do not. (6ohm parallel from black-grey9 to brown8)
• When both park and flasher circuits have their own resistors, flashers work always, park lights work never. (legal)
• When both park and flasher circuits share the same resistor, park lights work always, flashers work when park lights are off. No Hyperflash. (not legal, technically)

The tricky part is that the flasher and park circuits share a ground with the low-beam D1S headlights.

The two options I can think of at this juncture are this; first there might be a setting in VCDS that relates to the park and flasher circuits. If the flasher could be adjusted to an interrupt rather than a positive charge when the park lights are on, then the last option where the circuits share a resistor would work. Second, is there an alternative to the OSRAM 3457a LED replacement that would work better in a shared-, or dual-circuit application. I say this because the incandescent 3457a is a dual-filament. I'm not sure, my brain is sore, I'm going to eat and get some exercise.

Cheers

Larhal

Since it has a common ground you may want to try a seperate ground for each circut.

onceyougoavant

I think you're right Larhal, but unfortunately this circuitry is part of the headlight assembly. I only have access to the wires coming out of the assembly, where the shared ground has already been established. I'm not too keen to tear apart the headlight assembly and mess with the HID ballasts, leveling motors, etc. There are some CAN-BUS happy bulbs enroute, they should be here in a few days, but this is my last resort before putting everything back together and going back to incandescent bulbs.

I'll keep everyone posted on the outcomed.
Cheers.

onceyougoavant

It seems like things don't move very fast here, which is okay, but thought I'd post an update just in case there are others who are interested. I got the front markers and park lights working in LED with a combination of CANBUS bulbs and additional resistors. I have parts arriving today to complete the rear lights, and once everything is to my liking, I will post a comprehensive DIY with pictures, part numbers, and technique.

Thanks for checking the post, and I promise to have some relevant info posted soon!

Cheers

onceyougoavant

https://

Everything works, looks fantastic!


New Parts!

Resistor Mount front passenger

Resistor Mount front driver

Wire the resistor inline between the park signal, and ground.

Clean up those wires; I use zip-ties and electrical tape.

This where to access the signal/park bulb.

Had to use cutters to remove extruding part of socket. if you look closely you can see the part that is no longer there.

SC_09iduA

Looking fresh! Nice work my fellow MTn! My Avant is in need of a CANBUS decoder for my LED H7 low beams...I've been rocking HIDs but it's annoying needing to replace bulbs every year...granted, buy cheap and don't complain, right? Have any leads on how I can remove my dipped headlight error message even though the headlights are on? Also, man, I had to use an Emory-board (nail filer) to remove some material on the bulb housing to get it only half way in...still bright, still working, just ghetto and I'm not a fan of that...will need to modify the bulb-socket I think...nonetheless, looking good!