I replaced the burnt out hvac console lights (all 3 of them) in my 1998 Legacy Outback with high intensity 3mm warm white led's. The green rubbers from the old burnt out lights fit right over the new ones. The light level is perfect and looks stock when its in the car, meaning it's not too bright at night. I took the liberty to wash everything since it was sticky from years of coffee and who knows what... looked like beer. I don't even drink beer.
Once you have everything disassembled except the circuit board off of the face plate, you'll have to tug a little harder than you might want to pop it loose from the button faces. This sort of thing scares me, but after close examination, the buttons just pop onto the end of the switches. Do this carefully so you don't bend the other led's that illuminate when you select specific buttons.
3 led's in parallel
3.2-3.4 forward current
I calculated about 180 ohms at 14v. I put two 100 ohm resistors in series (200 ohms) just to be safe. See picture, below. Before you put the whole assembly back together, plug it into the car and make sure the led's all light up. If any don't, pull them off the board and re-install them 180 degrees from their prior orientation. Then pop the board into the face plate.
You can follow the traces on the board around and see which pins you need to put the resistors on. It's the end two on the passenger side. I trimmed the ribbon cable back a bit to make this easier.
I also put a red led in the ash tray light. Led: 20 mA, 3v foreward voltage, Resistor: 680 ohms.
Also, my Kenwood stereo display stopped working about 2 years ago. I've been flying by braille that long. There were no other instances on the internet 2 years ago. Then I happened to check for the problem yesterday and there was an overwhelming number of hits. Luckily someone figured out that a few resistors needed re-flowing, hence taking the dash apart. I thought I'd do the lights, too.
Edited by kanurys, 01 March 2012 - 09:33 PM.