Wiring Help F3 to LSX harness

[Gjohnson7]

Ok, hopefully there are some 240sx guys on here that can shed a little light on this for me. I am in the process for wiring the F3 plug into my LSX harness so that I can still operate my windshield wipers and other basic items. The plan is to wire in the LSX harness so that I can utilize the stock Nissan Fuse box and Relays as oppose to buying a separate fuse/relay setup for the Engine alone. This setup should be wire in just like any other Stand alone unit, but I'm pretty confused. The car is a 97 240sx that origianally had an Auto tranny.

I have this Pin out for the F3 plug and I have been trying to split it up from the Ka harness, but am I going about this the right way. I was thinking that the F3 plug probably had the fuse box and windshield wiper plugs wired into it so it would be better to remove it as a whole, but would I be better off just hacking off the F3 with about 6 inches of wires and wiring it into the LS harness or should I contiune the process of delooming the entire KA engine harness?

Also, has anyone successfuly hooked up their consult port using the F3? I will be running A/C controlled by the PCM as well so any help there would be greatly appreiciated.


Another member on Silviav8forums posted the following info:

Okay, so I'm working on the wiring now. Since I've gained a lot of knowledge from you guys (and I have plenty of questions left), I thought that I could give something back by documenting this as I go, and hopefully making it easier for those in the future.

I used a combination of the FSM and this document to do what I've done so far.

http://www.v8mongrel.com/240ss/files/f3plug95240sx.jpg

The items below that are in black, I have left in my connector for later use.
The items in red have been removed.
Items in Green, I am still undecided on, so please give feedback if you can.

- 1-black/red, ignition lead to injectors, coil
- 2- EMPTY
- 3-blue/red, rear defogger/electrical load signal
- 4-pink, washer switch
- 5-light green, ignition lead to wiper motor
- 6-light green/black, wiper motor high
- 7-light green/red, wiper motor low
- 8-brown, wiper off/int switch
- 9- EMPTY
- 10-black/yellow, fuel pump signal to F23, IACV-IAA
- 11-black/pink, fuel pump relay signal
- 12-orange, headlamp diode According to the schematic this is used by the ECM for a malfunction indicator?
- 13- EMPTY
- 14- EMPTY
- 15-purple/white, P/S oil pressure switch
- 16-yellow/black, AC switch
- 17-red, battery lead to ECCS relay I believe this wire and the associated relay can be removed?
- 18-brown, igniton lead to O2 sensors, EGRC solenoid, EVAP purge/vent solenoids, IACV, TPS
- 19- EMPTY
- 20-red, GST port (Can these be used to connect the OBDII port to the GM ECU?)
- 21-yellow, GST port
- 22-green, CONSULT port
- 23-green/white, CONSULT port
- 24-yellow/green, VSS signal
- 25-orange/blue, cooling fan high signal
- 26-yellow/red, tachometer
- 27-blue/yellow, wiper intermittent switch
- 28-yellow, temp gauge sending wire
- 29-black/white, ambient air temperature switch
- 30-orange, MIL lamp
- 31-blue/white, ASCD actuator power
- 32-blue, ASCD air valve
- 33-yellow/blue, 5th gear position switch
- 34-orange, start signal
- 35- EMPTY
- 36- EMPTY
- 37-orange/blue, recirculation relay
- 38-green/black, CONSULT port
- 39- EMPTY
- 40-green/orange, neutral position switch
- 41-blue/green, cooling fan low signal
- 42-purple, wiper variable intermittent switch
- 43-black/pink, triple pressure switch signal (leave for AC)?
- 44-blue/red, IACV-FICD signal
- 45-orange/black, triple pressure switch line
- 46-orange/blue, AC thermo control amp
- 47-green/yellow, ASCD release valve
- 48-blue/black, ASCD vacuum motor

Any of the AC leads can be removed if you are not retaining AC. Some of them may be removed anyway, but I am not planning on doing the AC until next year, so I am leaving the wires for now.

There is an additional plug for the ABS.
In this plug, there are three green wires that communication to the Nissan ECM. I'm told that these can be removed. There is also a wire that connects to pin 24 of the F3 plug. The VSS lead. This should stay connected to the ABS harness and connected with the F3 plug to the output of the Dakota Digital converter box.


*Disclaimer, my info is specific to the S14, your wiring may be different.

Once I start integrating this into the GM Harness, I'll add that information as well.

[g6civcx]

Straight from GM.

"LS-series" = LS1, LS2, LS6, etc.: LS Engines | LS327 Engine | LS1 Engine | LS6 Engine | LS3 Engine | LS 376/480 | LS 376/515 | LS7 Engine | LS9 Engine (http://www.gmperformanceparts.com/Parts/showcase_detail.jsp?engine=2)

"LSX" = LS eXtreme: GM Performance Parts | LSX Engines (http://www.gmperformanceparts.com/lsx/index.jsp)

[Gjohnson7]

Anyone with any Harness info?

[RUTH'LESSDET]

you need to hit up pxracing.com or ask him on silviav8

[Gjohnson7]

Alright man, I'l give that a shot.

How's that 350z treating you? You know you had one of the sickest LS Kouki builds ever, right?

[g6civcx]

Anyone with any Harness info?

I have all the harness info you will ever need or want.

I do not know what you are asking.

GM put LS-series engines in production cars. For example, if you said LS1/LS2/LS7 engine harness, I know what you're talking about.

When you say LSX, this is a custom GM Performance Part crate engine that was never mass produced in any vehicle.

Additionally, even though the factory LSX has bosses for fuel injectors, most of these engines are carbureted. Therefore, your question is even more confusing.


Tell me again. What engine do you have, and what car did it come from?

What do you want to do with the wiring?

[Gjohnson7]

My bad man, I can see the confusion there. I said LSX because all LS - series engines in cars and trucks have have the same basic setup when fuel injected, with the pcm being capable of stand alone status.

My engine is L33 HO 5.3L from 2006 Chevy Silverado. It is all aluminum with the LS6 heads and a T56 from a 2001 Trans am. The engine harness is a Truck harness as well out of the 06, I have the Tac module and pedal from that truck so that I can run Drive by wire. My PCM has already been tuned with Vats and all emissions removed and I have removed all unnecessary pins and wires from the Truck Harness.

At this point I am trying to integrate the Truck harness with the F3 plug on KA harness, so that I can still have windshield wipers and utilize the Nissan Factory Fuse box and Relays.

Do I need to just chop off the F3 plug and wire it in or are there more plugs connected to the F3 like the fuse box/ relays? If so do I need to de loom the entire Ka harness and try to remove the F3 plug wire by wire to make sure that everything stays intact?

[g6civcx]

Do I need to just chop off the F3 plug and wire it in or are there more plugs connected to the F3 like the fuse box/ relays? If so do I need to de loom the entire Ka harness and try to remove the F3 plug wire by wire to make sure that everything stays intact?

The windshield wiper by themselves is not bad.

The rest depends on how much of the stock fusebox and relay setup you want to reuse.

In general, this would be a medium difficulty job for me. It may be easier or harder for you depending on your ability with wiring and electronics in general.


First, I recommend you get an FSM for your year 240SX.

Second, if you have the time, I recommend pulling out your entire body and engine harness.

Go through and identify every single in these harnesses.

You don't have to remove existing wires that will not be used provided you properly insulate them.

Find out what you can re-use, and what you can reroute.


This is a fairly involved job since I'm not vested enough to do the work for you. You just need to do the legwork and pull the wiring diagram and go through every single wire.

You can ask any specific question you like.