I have a question not related to the Macan but thought you guys could help me. I bought a Mercedes GL450 for my wife and I am trying to change all the interior light bulbs from halogen to LED. Yes, and I thought only Porsche was still using the outdated yellow lights on their cars. Well, the light bulbs are 194 bulbs and I ordered Philips LED 194 which look amazing. The only problem is that when I installed them on the foot rest area for the front and rear passengers I realized they don't dim once you start the car and stay lit all the way. The way the Mercedes foot rest area works is that when you unlock the car the lights will illuminate the foot area but when you start the car they will dim and stay vey dimmed to just give you a bit of light. Well, since the LED that I bought don't dim you have to drive will full light on the foot area which is very annoying. Any thoughts on 194 LED bulbs that dim? Tks!!!!
I expect it would take a controller somewhere in the vehicle, if you can't find replacement LEDs that have the dimming controls built-in.
For traditional (incandescent) lights, you simply reduce the voltage (or limit the current) going to the bulb, and it burns cooler & emits less light. Like the old dimmers in houses, very simple device in-line with (or power source feed to) the bulb.
For LEDs, they are semiconductor devices that need a particular voltage bias / current value to operate and emit light. Not a voltage(current)/heat-light correlation like a traditional filament. A traditional dimmer or simple reduction in voltage/current generally will not work. LEDs can be "dimmed" by using Pulse Width Modulation (PWM) to vary the on/off cycle at high frequency. The longer the "off" time, the dimmer the overall light emission will appear. For more than you wanted to know, see: How to Dim an LED Light Quality | DigiKey
However, some household LED bulbs are now dimmable and incorporate the circuitry (e.g. PWM) into the bulb, or they use a special dimmer controller in the wall. I imagine our newer LED cars have a central dimming PWM controller that feeds all of the LEDs that are on the same circuit (e.g., all the interior bulbs dim in synch).
You can google to find LED dimmers on Amazon or eBay, but if not incorporated into the LED replacement bulb unit itself, you'll likely need to do some wiring tracing & mods... Here's an example: https://www.amazon.com/Auto-Meter-91...FEARW72M4KECKQ