Hi all!
This is my first topic, so hello everyone!
I wanted to share my latest project with You which was replacing whole power steering system from hydraulic to electric one. I had a issues with power steering pumps, leaking lines and even after replacing pump and reservoir I still saw some metal shavings in oil, so for me it was enough and I decided to go for EPS conversion. (How something can leak, if there is no oil in it
) I did this conversion on 2006 E92 with N52B25 engine. Everything is surprisingly simple.
Some informations in the beginning:
EPS was introduced in E89, so I managed to find some articles and technical documents on how it connect with rest of the vehicle. EPS rack itself has a module built in, so what we have to do is to connect power supply, and CAN wiring, so car can see the module. Then we will need to perform some coding, but everything is pretty straight forward, and in one day everything can be done. With this modification we can get also servotronic function. One important thing, for cars after as I remember 09.2009 there will be need for FSC code for Servotronic function SA216.
Parts needed:
- Electric power steering rack - best way is to get rack with parts of wiring included, it makes life a lot easier not to make electric connectors from scratch - I did this way)
- Around 2 meters of cables for power supply - mine were 16mm2 (get red and brown one for easy job),
- Around 3 meters of small in diameter wiring for CAN - we will need to connect PT-CAN (wake up line green with red stripe), and 2 Hi-Low CAN wires - they are wired together (blue with red stripe and red one),
- 100A flat fuse (From factory the B+ is taken directly from battery with 100A fuse, but we can use B+ connector under the hood which is not fused, so we have to add one) - to get everything clean, also special fuse housing can be used,
- Power supply connector - 61 13 9145405, with two 12 52 1436649
connectors,
- Wiring ends with hole (I do not know how to name this part - This is end of wire that you can put bolt through and attach to something
)
- CAN connector - 61 13 8383300 with three 61 13 0005197 connectors,
- PC with INPA, WinKFP, NCSExpert installed,
- Shorter accessory belt - can be found in RealOEM,
Good things to buy with this conversion:
- Tie rods,
- Tie rods dust covers,
Step 1: Removing old hydraulic system
Basically there is nothing to show. You will have to remove everything from system - Resevoir, all power steering lines, power steering pump, steering rack, do not forget also to remove power steering radiator which is in front of all radiators. Also accessory belt will need to be removed due to steering pump removal - that is why we will need shorter one.
Step 2: Installing EPS rack
I had to remove sway bar to get this done - Rest it straight forward. There are two steering rack bolts - 56Nm + 90deg, and tie rods nuts 80Nm. (If you are installing new tie rods - tie rod to rack 110Nm).
Step 3: Power Supply Wiring
If you already made the wiring, connect the power steering connector to rack. Now you have to connect somewhere the B+ and ground wire. I took the longer path around intake side (I was afraid to get the wiring hot on exhaust side). There is ground connection point on the left rail - so ground wire can be shorter - something around 1 meter - just put the cable there and secure with existing nut. I wired the B+ over the engine inside wiring tray above engine (there you can split the cable in half and put the 100A fuse to get it invisible, but easy to get), and put the B+ end on B+ connector that is provided on right side of the car (EPS has always +12V because of KL30 supply line)
B+ connection from EPS (red wire) on right hand side of car
Flat type fuse that I used:
Temporarily placed fuse for test purpose (before I bought the special housing for fuse)
Step 4: CAN wiring
Connect the wiring to steering rack motor, and wire this like power supply (You can put the wires together as a one piece for clean look), and wire them also inside wiring tray over the engine, but go with them to DME box on the right side of the car. There will be need some soldering action - you have to find exactly the same colors of the cable and solder new wiring to them wire by wire.
CAN and Power Supply wiring temporarily placed
So find:
PT-CAN wake up line - green with red stripe
CAN Hi and low wiring (they are wired together from factory) - blue with red stripe, and red wire
CAN wiring that I made:
Secure everything with eg. Isolation tape. Close box and be sure that every lock is properly closed - there cannot be any water residue!
Step 5: Get car to one piece
Reassemble everything - so under trays, put the wheels back on - mechanical and electrical part is done.
Step 6: Coding
Firstly open INPA and try to connect to EPS module. It should be visible because the PT-CAN and CAN will connect with EPS module. In INPA note down your part number of EPS.
If everything is visible, open WinKFP and by using P/N from INPA reflash the EPS module and write to it new VIN number (your car VIN). With that correct VIN number will be visible by car.
Last thing left is to wrote $1CB FA code to CAS and FRM by NCSExpert - without that step the EPS will not be visible in NCS, and we won’t be able to code it.
If everything is correct, you can download the TRC file from EPS, and in line „Variantencodierung_1” type the correct car type eg. „E90”, „E91”. You can also use there NCSDummy to read, change and finally create MAN file. From my point of view setting E92 steering option makes the steering heaviest from all of options - Personally I am driving on E90 setting.
Coding:
Code everything and EPS should operate properly. If there is connection error with some modules try to simply recode it. EPS connects with DME, DSC, SZL, CAS, KOMBI, JBBF.
Useful links:
http://weblog.pac1.net/_Documents/14...escription.pdf
Cheers!