Background
I've been racing with the factory harness and ECU for 7 years and I am Kswapping after my 3rd engine blew up (actively selling parts in the S2ki marketplace). The 2006 race car weights 2400lbs and has been gutted to the essentials with a cage and fire system. I've already de-pinned most of the non-essentials in the wiring harness to save weight (window motors, soft top motors, radio, lights etc). I chose a Haltech Nexus R3, but I want to maintain VSA and EPS. Note, when I say VSA, I really mean the ABS functionality. Traction control has been permanently disabled years ago.

Why not maintain full factory chassis harness for VSA/EPS?
Simplicity & weight savings. Haltech R3 doubles as an ECU and PDM. I can run the things I need on the race car from the ECU + CAN key pad such as wipers, fuel pump, surge tank, cool shirt, and defrost. I don't need 40lbs of wires that don't serve a purpose and they take up room. EPS/VSA will need their own dedicated power feed separate from Haltech.

EPS
EPS is pretty easy from what I can tell. There are two large gauge wires that feed power and two wires that I need to maintain. This will have its own dedicated power feed and then I need to map 2 wires from Haltech to give the speed and RPM.

• Vehicle speed: White/Black pin 2
• RPM: Blue wire pin 5

VSA
VSA is a bit more complicated. I've deduced all of the wires I need for sure such as power and speed sensors, and those I don't such as indicators, CAN, and DLC. There are two VSA fuses that are 30amps each, VSA Motor and VSA F/S. Not sure if both are needed since I can't figure out what is different between them.Don’t need

1. 2 GRY (K-line DLC)
2. 6 GNT/WHT (VSA Cluster sensor power)
3. 9 GRN/RED (Brake fluid level sensor)
4. 13 PNK (Warning light Electronic brake distribution indicator control)
5. 17 PNK/BLK (VSA Indicator)
6. 27 WHT (VSA Off switch)
7. 31LT GRN (Cluster Ground)
8. 35 GRN (VSA Indicator)
9. 44 BLU/RED (ABS Indicator)
10. 11 RED (CAN1 H)
11. 15 WHT (CAN 1L)
12. 25 RED (CAN2 L)
13. 29 WHT (CAN2 H)

Need

1. 1 WHT/BLU (Fuse 50 - power)
2. 4 BLK/YEL (Fuse 6 - power)
3. 16 BLK (GROUND)
4. 33 BLU (FR GROUND)
5. 34 GRN/BLK (FR +B)
6. 36YEL/RED (RL+ B)
7. 37 GRY/RED (RL GROUND)
8. 42 BLU/YEL (RR GROUND)
9. 43 GRN/WHT (RR + B)
10. 45 BLU/ORN (FL + B)
11. 46 BRN/WHT (FL GROUND)
12. 47 BLK (GROUND)

I appreciate any feedback/confirmation I am going in the right direction. Has anyone gone to a full standalone ECU and maintained EPS/VSA/ABS without a factory harness? What did you do to maintain it and how did you get it to work?

Cheers!

 

To get the EPS to work as oem, you'll need to make a hz map within the haltech based on speed. Otherwise, you'll have a steady state assist %.
If you search on s2ki, you'll find the hz to speed conversion needed.

As for the abs/vsa, you could spend a considerable amount of time to get the oem stuff working, but for a track car, its really a subpar system....or just go to the e90 mk5 abs that is MUCH better and also has vsa functionality. The abs unit itself is the same as the s2k, but is programable, unlike the s2k. Jason Wadsworth knows all the ins and outs of the system.

 

Thank you!

Yes I have a hz table I found that someone made for the EPS. I feel confident I can get that part working.

For ABS, unfortunately my racing rules for NASA prohibit me from modifying or replacing the OEM ABS system. The 2006+ has a Bosch MK60 (same as e90) which is pretty decent with my manual brake system. But I don't use the VSA. I'd love to be able to modify it and tune it but I can't. Alas, I just use the abs function, which is honestly only used in rain races and preventing flat spots. Worst case scenario I just keep the OEM harness in and feed it power.