LED lights - how to buy, which to buy?

Hi! I need to reduce 12V power consumption. I want to install LED bulbs for everything.
What is the power needed? I see H4 bulbs 3-8 watt with no radiator and I see 20-30 with radiator and a fan installed. What is the needed wattage for the same amount of light? Same question for W5W bulbs and turn sign ones. Thanx.

Regarding the headlight bulbs, I purchased something like these a while back: https://www.amazon.de/YuCarAc-Xenon-8000LM-Ersatz-Automodell/dp/B07TJWFX8K/ref=mp_s_a_1_6?keywords=led+h4&qid=1566487078&s=gateway&sr=8-6

But I must say, of the 2-3 LED bulbs I tested in the headlights, NONE of them worked well. The color was cool, and they were brighter for ME. But the optics of these lamps are simply not the same as the halogen bulb and therefore the reflector doesn’t focus the light correctly. In general, most LED headlight replacements create a lot of glare for other drivers.

I also purchased these for the license plate, which work great! Pay the extra money for PHILIPS. The Chinese brands break and flicker.

For the rear brake lights… no one has yet found a way to put LEDs here without getting all sorts of warnings on the dash. But there is a recent thread going on with some developments.



I converted my taillights to led today and also got the servlight, but it was an easy fix as all I needed to do was to put a 5w resistor between ground and brakelight on one of the connectors, so it will save you some energy but most important for me at least, it will look a little more “future” than before !


Interesting. So it gives SERV when converted to LEDs? Bad if so, cause I needed power saving above everything. What year is your twiz?

I have a 2018 but the 5w extra current draw from the resistor when you hit the brakes is still less then with bulbs.

What nominals are the resistors?

Why do you need to reduce the 12v power consumption? If your charger is working correctly then the traction battery charges the 12v battery, my voltage never changes even with lights, heated blanket, heated screen and phone and power box on.

I need to reduce power consumption exaclty because I have broken 12V charger. I installed extra 18Ah battery on parallel with the original 12V, in place of the windshield washer tank. I charge it externally. But I would like to reduce power consumption as well.

I recently received my ultracheap chinese LED lights, all types including brake lights. The results are puzzling.

First I installed LED W5Ws. Each LED W5W draws 0,21Ax14V. Original bulb draws 0,37x14V. LEDs have resistors on them. With original bulbs, in the GO mode with first light setting on, the car draws 3,3A of current. But with LEDs power comsumption actually INCREASED to 5,1A! WTF??

That’s pretty cool.