Help figuring out these wires

[myjeep3]

Doing a ls swap on my 04 LJ, and can't figure these 4 wires. I believe one if not all where connected to the passenger side engine block. Not sure if they are all groupd wires.

I was able to trace them and here is what I got.

- The 2 small black with blue strip go to the Fuel pump and vss and go to pin #4 on black pcm connector. Are these ground cables? I did combine them into 1 wire.

- The medium all black also goes to the Fuel pump. Is this also ground?
- The fat large wire go to the computer black connector, and connect to pin #30 and #31. Is this also ground??

Thanks!

 

[macleanflood]

Under the resources section are the Factory Service Manuals. Section 8w has complete wiring diagrams with colors and traces.

-Mac

 

[myjeep3]

Under the resources section are the Factory Service Manuals. Section 8w has complete wiring diagrams with colors and traces.

-Mac

I was able to identify the wire, and they are all ground.
Should I ground them to the engine block or battery negative?

 

[macleanflood]

Should I ground them to the engine block or battery negative?

Technically it's the same thing.

You might want to follow the wiring diagrams...some of those grounds run/ran through the PCM and were switched.

-Mac

 

[myjeep3]

Can someone with an 03-06 Taj confirm where to ground theses 4 wires?

 

[hear]

Can someone with an 03-06 Taj confirm where to ground theses 4 wires?

I don't have an 03-06, but I think the expectation is for you to confirm this against the FSM. If all the grounds were exactly the same, they probably wouldn't have multiple grounds at the PCM. At the beginning of each section is usually a writeup of how the circuit/sensor works. It might give you an indication of whether or not it works off a computer-switched ground.

Having said that, if I knew the answer I would just tell you.

 

[myjeep3]

More chopped wire:

All the connectors off of this plug were chopped off. Some of then go under the dash. Something to worry about on a LS Swap?

 

[myjeep3]

I don't have an 03-06, but I think the expectation is for you to confirm this against the FSM. If all the grounds were exactly the same, they probably wouldn't have multiple grounds at the PCM. At the beginning of each section is usually a writeup of how the circuit/sensor works. It might give you an indication of whether or not it works off a computer-switched ground.

Having said that, if I knew the answer I would just tell you.

Technically it's the same thing.

You might want to follow the wiring diagrams...some of those grounds run/ran through the PCM and were switched.

-Mac

Looked but can't find where the K4 wire goes. Though it was grounded on the side engine block. I was able to find the other wires which ground at G105, just can't find the K4.

 

[macleanflood]

Funny enough I was just messing with my battery temperature sensor... trying to manipulate the resistance values to trick the PCM to up the charge voltage.

K4 should be under the battery...I've got aftermarket fenders and can reach up and grab the sensor.

If you're not using the PCM to control alternator charge voltage then you can probably tape it off.

-Mac

 

[myjeep3]

Funny enough I was just messing with my battery temperature sensor... trying to manipulate the resistance values to trick the PCM to up the charge voltage.

K4 should be under the battery...I've got aftermarket fenders and can reach up and grab the sensor.

View attachment 547000

If you're not using the PCM to control alternator charge voltage then you can probably tape it off.

-Mac

Haaa, I see that, same color wire, thanks. so one of the 2 bk/lb wires I have cut went there, need to find were the other went. Looking at diagrams, K4 seems to be used by alot of systems.

Doing an LS swap, wouldn't the alternator charge b handled by the gm pcm?

 

[macleanflood]

Doing an LS swap, wouldn't the alternator charge b handled by the gm pcm?

Never done an LS swap. So generally I would assume so.

What are you planning on using the stock PCM for?

Any reason to retain it?

Not that I know what I'm doing or saying but I think I would be running everything to the GM computer.

-Mac

 

[myjeep3]

Never done an LS swap. So generally I would assume so.

What are you planning on using the stock PCM for?

Any reason to retain it?

Not that I know what I'm doing or saying but I think I would be running everything to the GM computer.

-Mac

Gauges

 

[myjeep3]

Need to finish wiring the underpass wires on my harness. I have 11 wires and have highted the wires I believe I will need.

Will run a relay for the TCC, do I need both #7, and #8 on the harness image below?
Also do I need the speedometer wire #2 on images below?

Got this relay switch at the yard, with 2 relays, can I use it for the TCC and Fan? They 35A

 

[hear]

The TCC doesn’t use a relay ordinarily (I’m 98% sure), why are you introducing one?

 

[myjeep3]

The TCC doesn’t use a relay ordinarily (I’m 98% sure), why are you introducing one?

Research show people using a relay and linking it to the jeep brake control wire.
Happy to hear how you would wire the TCC.

 

[myjeep3]

Need a 12V+ key hot wire to tap into for my ls tach emulator.
Behind the gloves box, there is a added circuit tap into fuse #10(instrument cluster) that was used for some sort of lighting unit I won't need, can that be used ?

 

[jonny jeep]

Yes. Fuse 10 is on the start/run output from the ignition switch.