The
problem is that with Canbus the resistance has to be low like the old bulbs. LEDs have a high resistance what results in a low current.
By lowering the resistance to say 20 Ohms there's some current going through this resistors and generate some power (Watt). Because of this the resistors cannot be placed on the LEDs itself.
When I started with the DRL LEDs the temperature of the original ceramic resitors became very high, appr. 150 degree Celsius indoor during testing. See picture below.
Due to this high temperature I decided to go for 50W resistors with an aluminium body for cooling. These resistors become appr. 40-50 degree Celsius during driving on a sunny day.
On YouTube I've seen a video where an additional computer fan for cooling the resistors is used. This isn't necessary I think.
The power consumption of my DRL LEDs with resistors is appr. 10W each. The old bulbs were 21W.