The GT1R BPC Harness is designed to make wiring in the Injector Dynamics BPC to your R35 GT-R a breeze. This PNP wiring kit comes offered in a few variations, but installation is nearly identical for every single version. Some interior removal will be required, and will depend on your BPC mounting location. The installation will be easier if you remove the passenger seat, passenger side kick panel trim, glove box, and passenger side rear seat bottom panel. You will also need to remove the battery to install some of the components, and it is advised to leave the battery disconnected throughout the installation process. The installation will be easy to visualize once we identify each of the components in the kit:
1: This is the main harness between the Injector Dynamics BPC and your fuel pump hat. Depending on if you are using the T1 hanger or a Radium hanger, the connector/wiring on the hat side will vary. The above pictured version is for the T1 hanger, and the Radium would be terminated in ring terminals. You will note that there is a small wire on the black 12ga lead of the BPC side connecting a 4ga ground wire. Take caution when handling to not stress this connection. The red, white, green, and black 12ga wires will mount on the BPC in this order:
2: This is a local ground strap for the BPC controller. The chassis side location will vary depending on if you are mounting the BPC under the passenger seat or in the trunk, but there are easy to find ground locations in each. The BPC side will connect to the "-" hole location, which you can see on the far right side of the unit:
If installing in the passenger floorboard area, there is a bolt and corresponding bolt hole that can be used for your grounding location on the door sill. Remove the bolt, sand any primer/paint off, and the ground cable can be routed as you see below:
3: Harness 3 will be the main communication cable from the BPC to the OEM Nissan fuel pump controller connector. This OEM connector is located inside the plastic panel by the passenger rear seat, and is easily accessed from the bottom side of the panel. You simply need to connect one end to the BPC mating connector and to the wire harness side of your OEM harness, in place of the factory module.
You will note that there is a single 2-pin DTM connector running the opposite direction of the OEM side connector. This will be utilized for CAN communications on an aftermarket ECU. If you ordered an M1 harness, we supply the CAN harness that will mate here and run up to the ECU location, which is harness 7 in the main image above.
4: The 4ga cable here will connect to the positive battery terminal and one terminal of the circuit breaker, as you can see below. The easiest method of routing is simply to run the cable underneath the small fuse box in front of the battery and over to the breaker. The breaker (6) will attach to the left side of the battery compartment in an existing hole, using the provided bolt:
6: This is the main power cable that will run from the opposite side of the circuit breaker, through the firewall, under the carpet, along the passenger kick panel, and back to the BPC. This cable will connect to the "+" location on the BPC. If you are mounting the BPC in the trunk, you will need to route the cable back through the rear bulkhead in one of the holes along the bottom. The firewall has a hole behind the battery that we open up, and finish with a grommet to suit:
This hole is typically used for passing a number of additional harnesses through, so you will need to determine the correct diameter and grommet to suit your needs.
7 and 8: We touched on harness 7 already, this is the CAN communication harness between the connector located close to the OEM Nissan fuel pump control module connector and the aftermarket ECU. We include our GT1R CAN Expander (9) for ease of incorporating a number of CAN harnesses at the ECU. You can see how the extension harness and CAN expander connect to the MoTeC adapter harness below. The connector on the MoTeC harness is labeled "PWR/CAN":
The CAN expander is not required to be used here, but does make things easier if you are using another CAN device at the ECU.
August 9, 2024 Amendment:
For those who purchased harnesses around March 2024 or later and are using the M1 harness we have implemented a change that is detailed here:
The harnesses set up for this change are clearly labeled on the packaging with a note and QR code linking to the above article. If you do not have this on the packaging, yours is an older version and will not require the additional work. If you are unsure please feel free to reach out to us.