Join Date: Jul 2012
Location: Portland, OR
My Ride: 2003 330CI Silver
Ak90 DIY Code your own transponder and have your own BMW key
This is my first diy so bare with me. I'm quite anal about typos, so I will do my best to proof read this before publishing. Yeah, if it doesn't make sense to you, it's probably a typo. I'm only going to cover EWS 3(EWS 2 is the same) since I don't have EWS 4 to show you guys. It requires a little bit of soldering but not that much harder.
Now I never liked working on cars. I'm a computer guy. I can fix anything that would be considered part of the electronics family. When it comes to cars, I'm clueless but I am picking things up as I go along. When you own a BMW, unless you're filthy rich or the job is something you yourself know would be an enormous task, you DIY and save money. If you have ever been robbed blind by the dealership for a key that looks like it costed less than $5 in materials to put together, don't worry, you're not alone.
I wouldn't say this DIY is for everybody. My total cost by the time I had a working key was $215 for a diamond shaped remote key. I'm pretty sure I could've gotten it down close to $175 or even less, but being my first time and not being sure if the AK90 worked or the blank key transponder thing works, I made sure whomever I bought it from had a refund policy. Now knowing that it does work, I won't care about that anymore. Also, I provide this service for people in the bay area, charging usually around $20-$30 to code a key, so the machine will eventually pay for itself. Anyways, let's get to work.
We need to remove the cover underneath the steering column to access EWS module. There are 3 phillips screws, and a plastic rivet.
After that there are 2 metal clips holding the front part of the cover up. They're on each side of the steering column cover where that gap occurs. I used a flat head to slide it in between the clip and it easily pops off.
Now you have a choice, you can unplug the gong, obd2 port, and floor light (which was what I did the first time) or leave them be and stick your head through whatever space you managed to open up and look up to the left at the EWS.
You'll need a 10mm socket to dismount EWS. What I did was loosen the nut furthest away from me, the one that holds the EWS up but is open ended. Unscrew the other nut all the way. Eventually you'll get that nut off and your EWS hangs there by its connector. Reach up there and feel around for the release tab on EWS. The release should be at the very end of the connector where it turns into wires. It comes off very easy.
Pull the EWS unit out. Now pop off the top of the case enclosing the circuitry itself. It flips open like a cigarette box, only its easier if you use both hands.
Pull the circuit board out of its casing by pushing in all 4 tabs on the connector side. I placed the open end on my chest at an angle, pushed in all 4 tabs and used my chest to help get the board out.
At first glance, it'll look like engine oil somehow got into the EWS. The coating on the board also looks wet, like it was going to be sticky or gooey when you touch it.
(This next step only applies to EWS2 and 3)
Next, have a razor blade, flat head, or something thin you can scrape with. That coating surrounds the metal contacts on the mcu chip that we need to connect to and will prevent electrical contacts. Take your tool and slowly scrape off the outside of the mcu chip, make sure you can see shiny metal on each pin. it doesn't have to be perfect, just as long as you expose metal. Once you're done, lets move to software.
Before you launch the software, plug the ak90 up to computer and place your key or transponder in the space allowed.
Launch the software. It'll beep then look for your transponder. Once done, push the "Test Key" button. It'll provide a little bit of info and ensures this is the key you want programmed.
Satisfied, click on the drop down menu on the right and select your mcu. Your mcu number is written on the mcu itself. Once you know your mcu type, pick it on menu.
Something similar to this should pop up
It's showing you how to connect the cables provided to your EWS. Mine was straightforward. Once connected, hit the read EWS button.
Once its done reading, save a copy of that file. Now after this point, if you forgot or needed info on the key and hit test key, it resets the info on read ews. instead of reading ews again, hit load that save file to save time.
Now select analyze EWS
Here you can add or delete keys, and modify VIN and mileage on EWS. If you feel you don't want to mess with anything, cancel out and lets go write you a new key.
Make sure your EWS data is loaded and present. Select write key.
Here you get to choose which slots to write the key to, and what type of transponder you have. My 2001 330ci had the 10030A EML. I believe the PCF 7930/35 belongs to previous generations prior to ews 3, I think. The first time I did this with virgin transponder, I selected a new slot. Ever since then I've experimented and have been successful in starting my car even after switching that same key to 2 different spots. Do what you feel most comfortable with. Then hit write.
Voila! You're done. Go ahead and try it out. With a virgin blank transponder, it didn't crank the 1st try. I was told you need to let it sit on ignition 2 for around 5 seconds for it to initialize or something then try and start. I got it on my 2nd try and was screaming for joy.
Last edited by NumbaOneNewb; 10-11-2012 at 09:07 PM.