Hey guys, I'm checking for all the information required to build my own harness for my race car and I was wondering what this connection was for?

Car: Civic 97 Coupe si
Used for: Drag racing only
Base Engine: B18C
Panel switch: ARC8000
Computer: Hondata S300 v2
Other: 16V battery

Goal: get rid of my OEM wiring and fuse box and make my own harness!



I will validate by tearing apart my OEM harness later this week, but I wanted to clarify what this really was for since I couldn't find what the exact purpose of that junction/loop connector on the web.

Thanks for any input!


Seb

 

More information is needed. How can anybody help you if you don't post what car/engine the harness is for?

 

it's a power splitter. i think it's used to split ig1 power to the 4 injectors. that or a blank unused plug.

 

Indeed, I'm building a harness for my B18C ODB2 and there's two closed connectors like this one on my actual harness. Hope this clarify more...

Seb

 

Your picture is grayscale. What wire colors are in the OEM junction connectors?

 

Thanks for the quick reply, I will post actual pictures tonight and include the pinout from ECU as well if I can get to this point.

Seb

 

Depending on year and model, if it is an OEM 14-P blue junction connector with Blk/Yel and Grn/Blk wires, it is used to split/distribute power (via the Blk/Yel wire) and ground (via the Grn/Blk wire).

Terminals grouped together are connected by the same bus bar.

Blk/Yel wires distribute power to some or all of the following:
• Evap control canister vent shut valve
• Evap purge control solenoid valve
• VSS
• Primary HO2S
• Secondary HO2S
• PCM
• Alternator

Grn/Blk wires distribute PCM sensor ground signals to some or all of the following:
• Fuel Tank Pressure sensor and Fuel Tank Temperature sensor
• TP sensor
• ECT sensor
• IAT sensor
• Primary HO2S
• EGR valve lift sensor


Depending on year and model, if it is an OEM 14-P gray junction connector with Yel/Blk or Yel/Red wire and Blk wires, it is used to split/distribute power (via Yel/Blk or Yel/Red wires) and ground (via Blk wires).

Terminals grouped together are connected by the same bus bar.

Yel/Blk or Yel/Red wires distribute power to the following:
• Individual fuel injectors
• IAC valve

Blk wires distribute ground from G101 to some or all the following:
• PGM-FI Main Relay
• VTEC Pressure
• Power Steering Pressure Switch
• Fuel Pressure Regulator Shut-Off Solenoid Valve
• Engine Coolant Temperature Switch
• VSS
• PCM

 

Thanks a lot tech8 really clarifies a lot of things

Seb

 

Here's the actual picture coming from my old engine harness. There's also a brown rectangular connector that seems to be doing the same thing closer to the ECU connectors where importants wire and some grounds are going to...

I just need to figure this out before starting to build my own with was is necessary to run my racecar.

Thanks!

Seb

 

Download the manual or google image search the wiring harness diagram for your year. It will tell you where each wire goes. Those are commonly referred to as "dead end plugs".

 

What car/year did the harness come from?

 

Thanks man!

Do you know where the power and ground are coming from? Ar both sent by the ECU ? Hondata S300 in my case...

I see PG1/PG2 (Ground) and LG1/LG2 (Logical Ground) but I can't seems to find a pin-out that sends 12v except for TPS and MAP that is corrected to 5v.

Thanks in advance!

Seb