As stated in the title I'm replacing the burnt out incandescent bulbs in my HU to LEDs. Wanted to check before I fry any circuits if I can supply a PWM signal into the illumination port for dimming the lights.

 

Which head unit do you have?

 

The Clarion unit from the 10AE, picture included.
After posting the question I just figured out that I need to increase voltage to the bulbs (they're 2.3V right now). Since I knew there was 12v going in i went with 12V grain of wheat incandescent bulbs only to find out they don't work, now i have some warm white LEDs ordered.

 

Sounds good. Make sure that the LEDs have the resistors built into them. If it works well, please do a writeup that can remain here for posterity.