Colors for SMT6 wiring

[E30godz]

Well as the wiring diagram for motronic 1.1 for the SMT-6 only shows 4 wires that need to be spliced, this shouldnt be too hard. I plan on using the glovebox flashlight connector for the power/ground source, so thats 2 wires left... the "V.A.F sensor" (air flow meter) and crankshaft sensor.. Does anyone know the colors of these wires in the wiring harness to the ECU? This help would be much appreciated.

[E30godz]

as im looking for a decent ground a power source, would just intertwining the wires together be ok for the short term? i mean just wrapped them around each other and twisting them together...i did this for the power and ground but im getting no signal...so its either a bad ground, or connection...whats the best way to break into the wiring harness connector to see what pins go to what wires?

[revo86]

Yea when I hooked up my smt-6 to my s50 it said there were only 4 wires too. WRONG, the perfect power manual sucks for the wiring, I wired it all up and there was no response from anything, I actually took the car to IDA automotive who I bought the unit from where using a scope he hooked the SMT-6 right, I was pissed cause I did it exactly how the diagrams showed, then I was strapped on the dyno, getting screwed paying for dyno time while he had to figure out how to hook up his own computer the right way...
goodluck...

[E30godz]

BEH!....i know others have gotton theres to work....wheres gstuning? i know some other cats on this board have been using it to varying degrees of success, but i cant seem to remember who!! please come forth!

[mspiegle]

yes, the wiring diagrams do suck. If you want to be sure, you need to buy the developer's CD which gives a full pinout of the SMT unit and will aid you much in getting it hooked up to your car...

[E30godz]

yea i have the pinout for my car...but i cant tell which wires go to which pin in the ECU connector...

[E30godz]

Sweet! i found the power and ground... a random red wire in the wiring harness supplies the power and the case of the ECU is what im using for a ground...the communications are up and running, but ive yet to find out how im going to break into the harness to find the other wires.

[E30godz]

more good news....i tracked the AFM wire down from the AFM itself, used a multimeter to find the wire that had the varying voltage from 0-5 volts, it was a yellow/gray wire....found that in the ECU harness and started soldering...last wire to find is the crankshaft sensor wire!..and i have no idea where to start hunting for it!

[mspiegle]

sounds like what I ended up doing... you need to get a copy of the ECU pinouts. If i remember correctly... there are 2 crank signals on the ecu harness... its gonna be on the 3rd row of pins, both will be next to each other, and somewhat in the middle. I might even go as far as saying it was a black and green wire... but i can't remember for sure. I think you can use either one, but don't quote me on that. All i know is that mine works after intercepting one of those signals.

Also, i had problems tapping power off the ECU harness for some reason. If your car runs like complete crap, get your power from elsewhere.

This info is also assuming you have a 325i (mine was an '87 with the newer 173 motronic).

Again, GET A BENTLEY OR SOME OTHER MANUAL WITH PINOUTS! Very important.

Good luck and let us know how it goes...

[E30godz]

interesting.
yea i have a bently etc etc...all the nessiscary documentation really. where did you end up tapping for power? i tapped from one and i THINK its running fine...hrmm, i wasnt looking for a change really. The solid black wire is used for the tach, i know...a exposed peice of wire kept rubbing against an exposed peice on the black wire and made the tach totally shut off...

so far it looks good, runs ok, i havent messed around with it much as i have no RPM reading...im slowly learning what all the abbrevations mean on the SMT-6 windows program, and learning what information im getting and modifying it does what...ill let yall know...ill TRY to green one and see...i cant imagine anything bad happening because of it..ive already blown 3 console light fuses though hrmm, oh and a headlight fuse..

[chesster6969]

So did anyone find a good way(read:easy) way to pop off the DME harness black plastic cover? Dont want to break anything unless I have too.

[gstuning]

Ok,

Since you have tha AFM signal, power and ground done, you now need the RPM signal, if you use the Black wire (RPM signal) you get no ignition tuning, but the black one would use MODE 10, and 6(teeth per revolution) , 1(teeth per fire)

If you havent unscrewed the ecu out from it´s stock place you should, it makes it all alot easier,

Do not just intertwine the wires, find the correct wires and solder them inplace, if you need to cut the original wire do it, you can always solder it back, when putting the smt6 harness to the ecu harness, the smt6 harness wires should be "leaving" the ecu. it makes putting the harnesses back and installation a whole lot cleaner,

To remove the black plastic cover you break the tie strap on the end of it, that loosens a little black cover, then you push the white plastic connector inside the cover out from the cover, effectivly pulling the black cover off the connector,

If you find the ignition wire you use 60 teeth per revolution and 20teeth per fire, that is the correct numbers for motronic on BMW´s
Also use MODE 1,

When you go on and do installations like this , be prepared to end up in little issues,
I don´t use power from the ecu harnesses on cars I do as I feel they have electrical distortion effect on the ignition signals wich go into the smt6,

The worst setup I have done was a totall custom job on a Turbo powered Wrangler 4.0 HO, I had no wiring information and we simply had to work from the ground up,
It took 12hours, but since I don´t charge for installation hours, just a pre determined cost, he payed no more then if it had taken 1hour,

Jobs vary that is true, but since you are installing it yourself and may not have all the equipment handy, then you may have issues,
Just talk to me when you get into problems :)

[E30godz]

cool!!! thanks!!

yes i have been soldering the wires in with much success now...but apparently imma have to find another power wire.

KC Ron Carter on Bimmerforums said that the Yellow and black wires were the crankshaft sensor wires..so im guessing its NOT the black one! What kind of voltage signal should i be getting from the "real" ignition signal?

Also, are there any other wires on the SMT-6 that could be used to give more control over there car? There seem to be quite a few extra ones!

I'm using the windows software version....and have a couple questions...all the numbes in the white boxes...is each number the percentage of increase/decrease fuel your giving the engine from stock? I believe this is the case, but just want to be certain. This is in analog mode. Thanks Gunni! you are quite a savior!

[E30godz]

ok, i believe i found the correct wire, it was a yellow one, i cut it, wired the yellow SMT wire to it, then wired the pink SMT wire to the other side....set the global settings to the ones you said, and.....the car wont start....it just cranks over and over...hrm?

[E30godz]

i went to the OTHER black wire...right beside the yellow one...i mistakingly took wire 48 instead of 47...runs well now! have full control over it!! all that is left to do is boost this saw'na bitch! For the wires that are now exposed, can i just put electrical tape over them? or is there a better way? heat shrink tubing is out of the question as its already soldered and all...