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Discussion Starter · #1 · (Edited)
I looked in the haynes manual (joke) and I looked in the wiring diagrams on the site but am having a hard time nailing down which wire provides the 12v + illumination to the window switches for each door..


anybody have any insight on the matter?

:thx
 

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What do I win, being the first? :cool:

It's actually not been easy to trace. The rear door switches, not being connected to an intelligent module in their respective doors, are fed by a dimmable PWM signal from the dimmable bus, which comes from the BCM and routes through the rear fuse block and goes to the doors on a BN/WH wire to the switch.

The front door switches, piggybacked on the door modules, don't seem to have ANY dimmable supply line going to them at all. The only power on that module is constant 12V, on an orange wire. Since the door modules have serial data connected to the BCM, I'm pretty sure the module handles dimming the local lamps in the switches. You might be able to confirm this by watching the window switches at night, and manipulate the dimming control, and see if the front window switches intensity lag the rear ones. That would correspond to the serial data comm delay.

Just another thing that could go wrong and drain a battery inadvertently. Learn something new every day!
 

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Roadie needs to upgraded to GOD status!:hail::hail:
 

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Discussion Starter · #9 ·
I am mounting a pre-wired Lumiled Superflux 4 chip LED behind each door handle and wanted to have it illuminate with all the rest of the standard interior lighting (minus the overhead lights)

would save me hours of running lots of wire and having to fish through the doors..
 

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For some reason, there is a dimmable incandescent lamp bus, and a separate LED dimmable bus - perhaps two different frequencies of PWM, or the incandescent dimmable bus is adjusted for the different VAverage versus brightness response curve. I should look at it with a scope someday.

The mod will be worth more if you have to work at it. :cool:

Have you already tried hooking one of these LEDs up to the other dimmable bus before you go through all that work?
 

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It goes through the rear block, but not through a fuse. Pick it up for a test at the headlamp switch, Purple/White wire.

Aha! Just found a snaeky bit of schematic on a page it should not have been. The DDM DOES have a LED illumination control wire, under the direction of the serial data link! There's a brown/white wire from the DDM to the seat memory switch lamp! Try that. It may not be designed to drive a LED though, just incandescent.

What happened when you hooked up the LED to the rear door window switch. Nothing? What did your meter read?
 

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Discussion Starter · #13 ·
I will break out the meter tomorrow but the LED didnt light when I hooked it up to ground and the brown/white wire at the rear pass. door..


also I dont have the heated memory seats (just the standard door lock and window switch functions
 

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Discussion Starter · #14 ·
ok I got the rear doors done and they work fine..

I started on the front passenger door and there is no brown/white wire (like the rear doors)

I checked all the pins and the only ones that make the LED light up is the two orange wires ( on different harnesses and both for battery) but they are on at all times.. :duh:

I couldnt find any wire that was hot when the dash lights were on and not when it was off :hissy::hissy:


I guess I will have to run 12+ to a switch behind the dash :mad:
 
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