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Old 06-21-2010, 10:24 PM   #6
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Join Date: Nov 2009
Location: Whitby, Ontario
Posts: 669
My Ride: 2009 335Xi Sedan
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Originally Posted by Arty View Post
PNP should do it.

The 10k Pull up is to make sure the transistor base comes up above the emitter when the switched GND is not there. TBH even without it the base will probably float up to the emitter voltage.


1) rinse and repeat the circuit for the other LEDs.
2) The pull up will stop any noise accidentally activating the LEDs. Unlikely to happen on such a short wire in a sparesly populated area.

Edit 2:

The Bentley manual looks wrong compared with the OP's description of how the cct behaves. It says in the diagram that a voltage below rail 15 is needed on pins 2-5 to turn on the LEDs.
That appears to be the E46 schematic.
This 6er schematic has replaced it now.
Perfect. I was worried about current draw and was looking @ using an inverter connected to a CMOS Bilateral switch (4066), but sounds like overkill based on your mods. The e46 schematics don't actually show the LEDs (couldn't frind them anywhere on WDS or Bently's), but they are pulled done by the transistors. I know it shows a 15vdc rail (actually battery voltage), but the part of the schematic that's missing is the circuitry that leads to the LEDs. I measured the vcc of the LEDs and it's around 2vdc (current design).

When open, the ground floats anywhere upto 7vdc (typcially around 2vdc), when closed; about .7vdc..... How much current can a std tx source (LEDs apparently like around 20mA)? I hooked up the LEDs to the dimmer power and ran from full power right down to 0vdc. They looked best @ around 6vdc.... Didn't measure current draw; should havem but was getting late and quite dark.....

Originally Posted by howie1971 View Post
I am sure you gave seen this from Delmarco but if not it might help

You sound like you know what you are doing so I am sure you will work it out.

Delamarco and i have been talking on this since he started (my Sig is in his credits) and we got it working on the bench @ that time. It was my interest in his DIY that got me started. Problem is; that NO ONE had gotten it to work off the bench and installed in the car. One of the other members up here and I have have spent considerable time tracing out the circuit and determining pin assignments (which BMW dealer couldn't find although there was a 2010 650Ci sitting in the showroom with this shifter installed.... LOL). Delmarco's work to retro the actual shifter has been extremely helpful in many aspects of the project. Gave me alot of great ideas. Going to use "P" button on top to replace current mechanical shiftlock, with electronic shiftlock; addressing numerous safety concerns....
My Rides:
2009 335i Xdrive

2000 Z3M Roadster

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