By: BiMmEr JoN (from BimmerForums.com)
Alright. I've been getting alot of e-mails and post about how I did my OBC conversion so I guess I'll finally spend the time to write about how it was done and how to do it.
FIRST :
Everyone who says it can't be done and those people who say it will cost a lot of money are about to be proven wrong. The most expensive part for anybody doing the conversion will be the actual computer and your time.
WHAT YOU WILL NEED :
1. The 18 button full OBC
2. A crap load of wire, I suggest getting a spool, or several spools of different color wire so that if you ever have to go back to look at the wires, it will be easier to look at.
3. Wire connectors - Female and Male or just the tube like connectors
4. Wire stripper / Crimper
5. Electrical connector - READ BELOW - VERY IMPORTANT
------------------------------------------------------------------------------------Here is the directions I originally recieved on how to do it. After these instructions, i will write how I actually tackled the project.
------------------------------------------------------------------------------------Just work accurate and check you're wiring and connections before you start (do you have all the right connections you supposed to have already, can you find the colours named in the instructions?? things like that)
and check you're connections again before connecting the battery again! Good luck.
So here it goes:
You got to have at least the clock/date/temp-module and preferable the checkcontrol or checkcontrol+temp.
Start with disconnecting the battery!!
The connectors:
X1070 = black connector on the OBC = it's the same as the clock/date/temp-module and up.
X1071 = white connector on the OBC
X17 = blue connector on you're Instrument-panel.
X16 = white connector on you're Instrument-panel.
Power:
move X1070-pin18 (+30) to X1071-pin8.
move X1070-pin17 (ground) to X1071-pin13.
Check that X1070-pin14 (+15) has power +12V with the ign. key in position 1&2! (it should be there already)
X1070-pin9 needs power with ign. key in position 2 only. Get it from X16-pin13 on you're Instrument-panel.
X1070-pin16 is for the lighting and should be there already.
The rest:
X1070-pin12 is for the Temp. sensor and already there.
X1070-pin10 & pin11 are for the gong (audible signal) and already connected.
X1070-pin4 is for the 'menu-step switch' in the turn signal handle (this ofcourse needs a handle with that option).
X1070-pin14 is for the connection to X607-pin4 (preheater-relais) (this ofcourse only in case you have the preheater option)
X1070-pin6 needs a wire to X17-pin26 in the Instrument-panel and it lights the 'check' light wich has to be added if you did not have Check Control before. If you had Check Control before, just check it.
X1071-pin6 needs a wire to X16-pin21 on the Instrument panel.
X1070-pin13 & pin15 are wired (keep them like that).
X1071-pin9 needs a wire to X17-pin10 on the Instrument panel.
X1070-pin8 needs a wire to the fusebox in the engine compartment where you connect it to the black/green wire (Central Locking Module) and in case you have Central Body Electronics you can connect the same wire to X10182-pin12 (black connector on the CBE-module).
Connect X1071-pin7 to a white/yellow wire somewhere around the foot area on the drivers side.
Connect X1071-pin5 to a white/violette (kinda light purple) wire, also around that same drivers side area. (there should be a free connection point for both).
Connect X1071-pin1 to connector X1659-pin15 from the Electronic Car Alarm/Immobiliser (BMW name in German = EWS) (in case you don't have the ECA/I system connect X1071-pin1 to a black/violette wire on the passenger side.
If you already have Check Control, check the next connections:
X1070-pin3 (white/blue wire) to X1074-pin5 (Check Control Mod.)
X1070-pin4 (white/green wire) to X1074-pin7 (CCM).
X1070-pin5 (white/gray wire) to X1074-pin3 (CCM).
Congratulations, you're On Board Computer should work now!! and you're grass will be a lot greener too.
(if the battery is connected of course)
If however, everthings works except the Check Control, you're OBC needs to be re-configured for you're car. That can be done at you're local BMW dealer.
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WHAT I DID :
*****Very Important*****
You must go to a junkyard that has BMW’s. The most important part and I can’t stress this enough is getting the other electrical connector that the 18 button OBC uses. If you do your homework, you will see that your existing TEMP/CHECK control computer only has 1 harness going into it. The full 18 button OBC has 2 harnesses. That’s only part of the bad story. The second part is that the you have to cut wires from your original harness and re-tap them to the new harness and then run wires from different parts of the car to the new harness. (DON’T FLIP OUT YET, THAT’S NOT TO HARD). Making your own connector would be very hard and you always run the risk or shorting out something so I strongly suggest getting the harness out of another junked BMW.
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Step 1 :
Don’t start taking apart your car immediately. What I did was sit down with those instructions I put up before and deciphered them. I drew an electrical diagram of of both connectors and drew wires coming from each pin and labeled where each wire went I the car. THIS HELPED A LOT. I lost a couple of the diagrams but I have no idea how I would post up these diagrams I drew. But I suggest doing that. Here is a sample of what I did. Label what the function of the wire does to incase you ever need to refer back to it later on.
PIN 1 -------------------------------------- GOES TO PIN 23(DOES THIS)
PIN 2 -------------------------------------- GOES TO PIN 39(DOES THIS)
PIN 3 -------------------------------------- GOES TO WHEREVER (DOES THIS)
PIN 4 -------------------------------------- GOES SOMEWHERE (DOES THIS)
PIN 5 -------------------------------------- GOES HERE (DOES THIS)
PIN 6 -------------------------------------- GOES THERE (DOES THIS)
PIN 7 -------------------------------------- AND (DOES THIS)
PIN 8 -------------------------------------- YOU (DOES THIS)
PIN 9 -------------------------------------- GET THE POINT (DOES THIS)
Understand the directions :
X1070 – When you see this, it is referring to the Black connector that your car should already have. This connector should have 18 pins on it.
X1071 – When you see this, it is referring to the WHITE connector that you will need to get from a junkyard. It should also have 18 pins.
X17 – when you see this, it is referring to the BLUE connector that is attached to the instrument cluster
X16 – When you see this it is referring to the WHITE connector on the back of the instrument cluster.
Step 2 :
Print the original directions on top and then read the rest. I am going to explain how to read this guys directions .
Step 3 :
Remove your instrument cluster. This is done by removing the 2 screw at the top of the cluster and wedging it out between the steering wheel and the dash. Once this is done, disconnect all the connectors from the back of the cluster. This will make it a lot easier.
Step 4 :
Ok, I’m looking at the section that says POWER.
Its really self explanatory from here. If you followed my directions and drew a wire diagram the rest of these directions will be super easy. Just move the wires it says and attach the wires it says to wherever it says.
You have to fish wires from the instrument cluster down to the computer. They went down fairly easy for me hopefully it will for you.
GOOD LUCK.
HOPE IT WORKS. I’M NOT TAKING ANY RESPONSIBILITY FOR YOU MESSIN UP MASSIVE AMOUNTS OF SH*T ON YOUR CAR. I’D ONLY TRY IT IF YOU HAVE SOME KNOWLEDGY IN ELECTRICAL STUFF. DON’T DO IT UNLESS YOUR CONFIDENT YOU CAN. IF YOU HAVE ANY DOUBTS, DON’T EVEN TRY.
Diagram