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Steve @ BMS/Fuel-It! Steve @ BMS/Fuel-It! is offline
Posts: 18,427
Join Date: Oct 2012
Car: 135i
Default 06-27-2016, 01:52 PM

Note this post is a living document. Will update with additional photos and info as we can.

Directions for older Stage1 or Stage2 to JB4 upgrade kit:

If you ordered a full JB4 system and are not upgrading an existing Stage1 or Stage1 system disregard this section.

When upgrading an installed Stage2 system to a JB4 you're going to first remove all wires from the DME connection putting those connections back to stock within the DME to avoid mixing up wire positions. Also note when upgrading a Stage2 system 7 loose Stage2 wires will be cut off the JB4 harness. We suggest cutting them around 6" from the control box in case you accidentally cut the off the single loose wire that needs to remain. Alternatively you could just cover each end in tape and bundle them together out of the way. The one loose that will remain is the purple male wire going to JB4#19.

The JB4 upgrade kit includes 4 new wires. A pair of green and a pair of purple.

The green wires are plugged in to the JB4 connector as indicated:
Green female JB4#8
Green male JB4#14

The purple pair connects to:
Purple female JB4#9
Purple male JB4#19 (note those upgrading from a Stage2 system already have a purple male wire in the spot and reuse that wire)

There is a single long green/brown wire that has a small black MOLEX connector on it. This is for the OBDII CANbus directions. It installs as follows:
Green wire JB4#2
Brown wire JB4#15

Install directions for JB4 N63/S63:

1) Install the TMAP connectors and control box per the n63 Stage1 installation guide:
2) Install the OBDII Cable per the s63tu JB4 guide:
3) The two remaining pair of wires, green and purple, are only needed when using E85 fuels. They attach to the DME similar to the obsoleted N63 Stage2. Note only the green/purple positions in the video are accurate. BCM wires are NOT shown in video.

Fuel control:

Circuit A (purple pair):
Purple female from JB4#9 to DME black connector #45
Purple male from JB4#19 to wire removed above

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Circuit B (green pair):
Green female from JB4#8 to DME gray connector #44
Green male from JB4#14 to wire removed above

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Optional BCM

Cliff notes:

Brown BCM female to DME black connector #17
Black BCM female to DME gray connector #6
Ground to strut brace
blue dsub pin to DB25#1
Red to switched 12v in relay box fuse tap

For those running E85 or race gas the BCM (boost control module) will help the JB4 directly drive the wastegates maximizing their potential.

1) Blue wire with DSUB pin connects to JB4#1. If there is already a wire in there from a previous Stage2 install then just splice them together

2) Ground attaches to the strut bolt or any suitable grounding point

3) Red connects to 12v switched power which is found inside the fuse/delay box as shown. Remove the fuse and then slide it back in along with the BCM wire as a "fuse tap".
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4) The brown loop connects to the DME black connector spot #17. Note wire in photo is incorrectly shown as blue.
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5) The black wire loop connects to the DME gray connector #6
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Reference video from obsoleted N63 Stage2 system to show how DME connectors come apart and how to attach wires. Use this video as a guide for how to access pins but note black/brown BCM wires on N63/S63 JB4 go in DIFFERENT locations.

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Video of our Stage 2 LPFP upgrade installation.

BMS products labeled for use only in competition racing vehicles may only be used on competition racing vehicles operated exclusively on a closed course in conjunction with a sanctioned racing event, in accordance with all federal and state laws, and may never be operated on public roads/highways.
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