X5 Servotronic Retrofit--Success!

[jayrockstar]

First, I'd like to thank all the contributors to this fine forum. Utilized a wealth of useful information from others who were nice enough to post their experiences in owning an e53. It's made my ownership of a 2003 4.4i bearable, and almost cost effective!

Second a little history on this X5:
2003, 173K currently, purchased CPO with 46K in 2006. Valve cover gaskets, front timing cover gaskets done 75K, covered under CPO. After 100K self maintenance includes: Plugs and Coils, Water Pump, Alternator, belts, full cooling replacement (radiator, all hoses, and reservoir tank). Two full sets of front control arm bushings (one powerflex), full bilstein hd yellow set, cd player upgrade, full 4.6is body kit retrofit, 19" Style 63's--multiple sets of 19" rubber, and multiple sets of brake pads and rotors (running meyle rotors, and cool carbon pads--me likey. The list is long and distinguished, and proud to say all work was done by me. (More out of necessity, as I can't imagine what all the labor for the aforementioned work would have tallied.)

Which brings me to the current subject in the title bar--

My wife got into a fender bender recently and broke the left steering tie rod, (among other issues) and when I sourced parts for a new steering rack, the idea to replace the rack with a servotronic unit came to mind. I drove a 4.8is and loved the steering, and the addition of fatter rubber in the front made parking lots for my wife a minor ordeal (she absolutely loves the newer electronically assisted steering--Bleh!) Got the rack, with the servotronic servo, supported the engine (love harbor freight), lowered the front subframe, and installed the new rack. And then pushed off into to sea of abundant misinformation...

My X5 had the servotronic plug already sitting in the engine bay. It's a two wire female plug, sitting unused near the front of drivers side shock tower. If you are contemplating this upgrade, go check to see if your plug is waiting. Got the plug? good, we can share my upgrade experience. Don't got plug? Don't fret, still doable, just can't give first person experience on how to do it (will show you how later.) I cut the brittle plastic tie that held the bundled wire together and managed to plug it directly in to the servo on the rack with a positive "click". And like a giddy school child, (while patting myself on the back) started the car to see how easy it was NOT to upgrade my rack. Turned perfectly, and smoothly, but with full force needed to do so. There was clearly no signal to make the steering input variable.

Which leads us into the pit of despair...and coding with the X5.

I am computer savvy, and hardware savvy, and confident in connecting devices on a PC. And this was a royal pain in the ass. Let me stop you here. If you are not comfortable with any of the electronic side of the world, get your tools, install the rack, and then get your computer savvy, "already coded an X5" friend, and his (or her!) 12 pack and show them this post.

Don't have a friend? Proceed with caution:

Going to cut thru the misinformation and tell you how I got it done. More than one way, I'm sure, to do it, and looking forward to others' input.

1) You need to get a cable to connect. I bought this one for $23.99:

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

**This will not work on an e53 X5, without bridging pins 7 and 8**. I drilled a small hole in the plastic case near pins 7 & 8, and soldered a solid wire from each of the terminals. Routed the wire thru the hole, reassembled the case, and connected to a switch that was hot glue gunned to the outside. Wha-Lah, a cable-switchable- INPA K+CAN K+DCAN-Car-Diagnostic-Tool-Cable, that you should have been to buy from somewhere, No? If you do this one step, you will save yourself hours (days for me) wonder why your X5's Ecu won't talk to your software. Which is now next.

You need Software on your Pc:

I got mine (bmw coding pack) from Bimmerforums. Here:

All BMWs Download Links to Softwares - Page 469 - Bimmerfest - BMW Forums

Ask nicely. Might say Thanks.. Spin the Drum on the wall and say "I.I.I.I.I....Want the knife"

While your asking, ask for the link to the latest e53 datum update. Two downloads, Two different installation procedures. Know how, and be familiar with the procedure before you start. (Or buy an extra six pack for "already-coded-e53 with-ncs-expert-friend")

**Now is a good time to enter a disclaimer. The software your asking for is a very powerful tool, that can brick electronic modules on your X5, costing multiple hundreds to replace. Research outside this post, and go slow. Not responsible for bricking, proceed with caution, etc.**

Links will be sent, and they will be downloadable in .rar format, so you need a free unzipper: I used 7-zip available Here:

7zip

Install as per instructions within the coding pack. Try Inpa first, look for the two black dots when you open the program to make sure computer/software/ecu are having a proper threesome.

Now you have the tools to properly grenade the ecu's on the X5.

My original plan was to recode the zcs and add the $216A Servotronic code to the zcs, and recode both locations in the EWS and KMBI modules. Our e53 are bastard children in that the DO NOT utilize the newer FA system of car option coding, even though our production dates would make it seem so. A good explaination here:

https://www.bimmerforums.com/forum/a...4&d=1377918669

I downloaded the ZCS Coder program from Here:

https://www.bimmerforums.com/forum/s...92-ZCS-Decoder

and was going to reprogram both modules, when I found this:

http://www.bimmerforums.com/forum/sh...g-box-retrofit

Seems if you are prewired in the engine bay with the two pin servotronic connection, you don't need to reprogram the ZCS, just activate the servotronic option by checking the box from the GM3_E53.CO4 module using NCS expert. I used the NCS Dummy and followed the included video in the coding packet. ***Servotronic signal output is controlled by the ECU, independent of if the X5 was coded from the factory with the option!** The same link above details how to wire the servotronic if you don't have a High GM module, of which I have no first-hand experience in installing.

Recode per instructional video included in your coding packet, and success when starting the car--I have servotronic on my e53!

Lots of info here, and I relish in the fact I accomplished something that my indy-BMW shop (that I was prepared to pay dearly) said was impossible. Good Luck, and happy to contribute my experience with those who helped me so much over the years! Cheers!