acr2001

I'm going to post a DIY when this is done if anyone is interested.

I'm adding LEDs to the vent knobs (the airflow knobs on each vent to turn them on and off). They come stock on the C320. Other vehicles are missing the LEDs and the wiring.

My question: Does anyone know where I can tap a power source near the dash that only turns on when the lights are on? It's not a lot of amperage just 4 LEDs with resistors. Is there a power source where the vents would plug in if i had that option?

Thanks

samaritrey

no clue but is it really worth it? i have mine turned down all the way because i think they are annoying lol
just had a thought what about the power for the ash tray light? it also dims with the knob on the IC.

jcnash

That's be a great DIY!

The ashtray light is probably the closest source which would suit the requirements, or the cigarette lighter surround light.

Looking forward to youre DIY. Dont forget to take pics..

acr2001

Honestly I'm doing it because I was looking for a simple project to waste some time.

Ash tray light sounds like an idea, I just don't want to overload the circuit. Is that light an LED or a bulb?
I wonder if I can tap into that voltage source directly without resistors on the LEDs....

samaritrey

on my car the lights in the vents and ashtray and cig lighter surround are bulbs as far as i know. i would say you need to get your volt meter out and start investigating.

jcnash

Bulbs...

Theyre both 12V 0.5A incandescent bulbs. So you will definitely need resistors to knock the voltage down to a voltage which the LED can handle.

You wont need load balancers because the SAM doesn't monitor those lights..so varying power draw wont be a problem

acr2001

Photos coming tomorrow with any luck.

Soldered some surface mount LEDs to some thin wires. They get shoved into the back of the thumb wheel, positioned so that the light faces the center of the symbol on the wheel, and then the thumb wheel is filled with hot glue locking the LED in place.

Next question is how to remove the side vents. Already removed the center vent.

I'm hoping I can snake the wire from the ash tray to the top of the dash without removing my comand unit... otherwise this is a hell of a lot of work for these lights. I'm going to use wire taps so that this is all totally reversible (no factory wires spliced or cut).

samaritrey

i would remove the command for a cleaner install sorry. and the side vents as far as i know come out the same way as the center.

jcnash

You have to also make sure that the LED's are the diffused variety and not the focussed type.

This will ensure even spread of the light across the entire area of the knob and not concentrate it in the center.

acr2001

Center vents done!

This worked out a lot better than I expected. Haven't put it in the car yet, but the light looks identical to stock as far as I can tell.

Have to route the wires into the thumb wheels carefully so that they can go through their full motion without putting stress on the wires.
Positioned the LEDs very carefully for the right light pattern and then held in place by injecting hot glue into the thumb wheel - but it can't get between the LED and the front of the wheel!

Everything is held together with hot glue (which actually worked well).

Resistors (2 per LED): 3.65k ohm 1/4W 1% Metal Film Resistors (had these from a previous project and doubling them in parallel works fine)
LEDs: Osram LYT670 Yellow SMT Bought from this seller: http://cgi.ebay.com/ws/eBayISAPI.dll...m=110429887995

acr2001

Doesn't look much different from the stock setup, does it?

holycaoAMG

acr2001

Does the thumb wheel for the rear seats light up?
I was thinking about doing it... but I think the work involved may be pushing it

holycaoAMG

To be honest, i really never look back there at night, so i dont remember if they light up or not. i personally dont think its really worth it doing the rear knob even if you can. GL

sinaa

nice DIY thanks

LILBENZ230

Was this a C320-only thing or was this something they deleted during the 2005 facelift? Because they progressively deleted stuff from 2005 to 2007, as you already know.

acr2001

I could be wrong, but I think it was a C320 only thing as part of the advanced HVAC system (with the charcoal filter, LCD instead of the knobs, sun sensor, etc)

I also added the LEDs back to the symbols around the headlight switch (using the same LEDs and resistors) but that was much easier as they only had to be soldered to the existing leads on the circuit board. I think they deleted those lights in 2005.

I'm surprised the 07's still include a windshield

If I completely lose my mind I might install some footwell lighting too (but it would be very dim - same as MB does stock in the E class)

AdidasC230

what did they start deleting? Id like more info on that, if you could

Glyn M Ruck

I'm impressed - neat job - how hot do the resistors run?

acr2001

Thanks. They barely get warm to the touch.

Glyn M Ruck

Great!

jcnash

Awesome.

The end result is pretty cool.

Definitely going on my list of upcoming mods.

payam81

This is fantastic!

Curious, do you run them off a 12V adapter when testing them outside or off a 12V battery?

jcnash

Wait a minute....just noticed. Where is your center blue knob that controls outside air quantity??

LILBENZ230

Deleted.. I believe even before the 2005 facelift, but I could be wrong. ACR seems much more knowledgeable about what was removed each year than I am.

I know that 2005 was the last year of real leather inserts. 2006 and 2007 cars had all MB-Tex, unless ordered with leather. At some point the tow-away sensor was deleted after 2005, but not sure if that was 2006 or 2007. The LEDs on the headlight controls were deleted in 2005. But from another thread on this board, some 2005s (early ones, I guess) had them. My car has a production date of 1/25/2005 and does not have LEDs in the headlight switch.

2005 was the last year of standard side airbags in the rear doors. 2006-2007 had this as an option.

The 2007 cars got cheap door lock tabs, and the surround on the headlight switch was black regardless of interior color.

ACR might want to chime in here.