Looking for where the Red (A4), Purple (B4) & Pink (F4) physically connect on the LS1 side of the Bulkhead connector. Car is '91 RS with LS1 & 4L60E. I believe B4 goes directly to the starter S terminal. Thank you.

 

The 10AWG Red Wire would go to Constant 12V+ /Battery.
The 10AWG Purple Wire would go to the Starter Motor Solenoid to crank the Engine.
The 10AWG Pink Wire supplies Switched/ Ignition 12V+ ...Depending on who made the Harness it could go to anything requiring Ignition 12V+.

In my own harnesses, I remove the Load from that Wire/ Circuit...
and just use it to trigger multiple Relays for Circuits that need Ignition 12V+.

 

Thank you. So, the red could connect directly to the battery, purple to starter S terminal and pink to where....alternator? Just curious where these 3 specifically connected to on the original 3rd gen. Thank you and Happy Turkey Day!

 

No NOT the Alternator.

The 10AWG Pink Wire originally went to the Ignition-Coil for the Distributor.

 

So where should the 10AWG pink go on the LS1? Also, where did the 10AWG red connect to on the original 3rd gen. Thank you again!

 

The 10 AWG pink (terminal F4) goes nowhere now. Just dead end it.

It could be used if you want, but you'd have to invent a purpose for it. That wire has +12V when the key switch is in the RUN or CRANK position. I use it to trigger a relay that powers up my engine fuse center. And that's the same kind of thing vorteciroc uses it for if I understand right.

 

By the way, tape it up safe because it cannot be disabled and will always be live when key is in RUN or CRANK. It is wired straight back to a power source with no fuse (does not go thru the fuse panel). If that wire is shorted to ground you'll either get a fire, or you'll blow a primary fusible link and disable the car.

 

The red wire connects to the same post on the starter as your positive battery cable...

 

I use that Pink Wire to trigger Relays that should only be ON with the Ignition ON...
Like I said in Post #2:
For example, I Build my Bussed Electrical Center with 2 Relays that provide power to the Ignition-Coils...
That 10AWG Pink Wire triggers the 2 Relays for the Ignition-Coils.

Regarding the 10AWG Red Wire:
It connects to the Starter-Motor, in the same place as the Positive Battery Cable.

 

Perfect...thx all!

 

If I'm not mistaken, red (!0 AWG) on the 3rd gen connected to the starter with the fusible links...do I still need or should I still use the fusible links or just straight 10 AWG wire? Also should I still connect the (12 AWG") red from G5 of C100 to that same post?

 

Either a Mega-Fuse... or a Fusible-Link.

 

Yeah, absolutely use fusible links...

 

What are you using for Power Distribution?

I am guessing that you are still using at least some of the original (IP-BEC) Instrument-Panel Bussed Electrical-Center (Fuse Panel under the Dash/ Gauges).
Did you add a (U-BEC) Under-Hood Bussed Electrical-Center (Fuse Panel under the Hood) for the Engine Management/ EFI and related Cicuits?

 

Actually... Did you purchase a pre-made Engine Wiring-Harness for an LS1 Engine-Swap for a Third-Gen F-Body?
Or did you make one? ...modifying a Universal LS1 Wiring-Harness, to work in a Third-Gen?

I am curious if Wiring and Power Distribution was provided...
or if you are now trying to piece everything together.

 

All good now...I did use a combo of a "painless harness" for the LS1 and my old C100 from the 91 RS. Thanks for all the help!

 

The prior owner (who claimed to be an electrician), left the under dash area looking like homemade explosives!

 

LOL, I was going to complain about the quality of most Painless products...
But there is already a bunch of questionable Splices under there.

First I though you were pointing to the Yellow Air Bag/ SIR Connector...
Now I think you are referring to 3 different Connectors?
The Second small Connector is for the VAT System, and is very delicate!
I would hate to find Splices in that Circuit.
The last image shows the Connector for Power-Accessory distribution.

 

"Electrician", huh?...

 

Crazy right?! Yeah, those arrows were from another post; Everything will be properly insulated, sealed and cleaned up. Thank again!

 

Excellent!
Cover up all those Wires with exposed Copper Conductor.


I know that US Residential Electrical Systems are very basic compared to the Electrical Systems of Motor-Vehicles...
But there should be no excuse for exposed Wire Conductors.

Everyone who has worked on their own Home Electrical Wiring...
Has opened an In-Wall Box/ Gang, and seen some Wiring with lazy work/ exposed Wire Conductors.
But just because something is common, does not make that something exceptable/ correct.

I really hate to see Electrical "Hack-Jobs"!

 

Excellent!
Cover up all those Wires with exposed Copper Conductor.



People never cease to amaze me!

 

OK just getting back to this project since busy with family and holidays! So engine cranks but doesn't turn over. In "acc" mode, fuel injector wires draw 12V, but in "crank" mode, they only draw 7v, so the wire from the starter which is now connected to the yellow 10AWG wire must be incorrect? I think that has to be connected to constant 12v wire. Can someone advise? Here are the lovely 10 AWG wires (red, yellow, pink, orange) under the steering column (which will all be repaired once the correct connections are determined). Thank you!

 

I am sorry to be that Guy...

But you should really always repair what is right in front of your face, before trying to diagnose the more complex issues.

 

That's the plan, but in the meantime, can you answer the question please? Which of these (exposed!) 10 AWG wires (red, yellow, pink, orange) under the steering column is the constant 12v wire?

 

You've already been told.

 

You did...my bad. So when I turn the key, starter is activated, car cranks...sometimes it "turns over" for a second, but that's it. Injectors & coils are at 12v in run position and drop to 10v in crank position, but engine does not turn over. Fuel pressure is at 60 psi. I have a relay bypassing the NSS; I bypass the starter enable relay as shown in first pic below and bypassed the VATS (with PASSkey II). Could the issue be with the gear selector switch (org/blk and blk/wht wires)? Right now I have them connected from the PCM to the switch. Thank you.

P.S. Again, this is an LS1 with 4L60E.

 

What did you do to repair the damaged wires? That was a lot of damage, not just to the insulation but the wires itself. It has to be removed and replaced. You're in for a whole lot of work.....

I think you're super anxious to get your car started but you're just not there yet. That bundle of wires is a lot of primary wires that affect the power supply for a lot of things on the car. You've got all winter bud, just take your time to do it right and you'll be driving come spring.

 

Thank you ... the three-10AWG (pink, yellow, orange) wires that were stripped/damaged are good now and producing proper voltages. Ignition switch is also new. I have plenty other things to accomplish before it hits the road, but for now just want it to run. Anyone have any suggestions to why I am not turning over? I provided the status in post #27. If there are other questions that will help with diagnosing and offering suggestions, please provide. Thank you.

 

When you say "Ignition Switch" are you referring to the actual Ignition Switch...
or the Lock Cylinder for the Ignition Switch?

 

Actual

 

Is it just my aging eyes or is the starter solenoid (purple) re-wired directly to the tiny little wires for the VATS key resistor? And if that's not so, then what is it connected to?

 

The image you reposted is what I was faced with when I got the car. It does not look like that anymore! The starter solenoid is connected to a relay that is in turn connected to the yellow 10AWG wire in that same image. See schematic below. There is also a orange/black & black/white wire off the relay which are capped. The orange/black & black/white wires that I have connected are connected to the gear selector switch. I believe the other end of those wires connect to the 4L60E harness. Is that correct?

​​​​​​​

 

I believe I may still have a VATs bypass issue even though I added a VATs bypass module, so I may try to disable it in the PCM. Is there something I can buy (HP Tune?) that will enable me to hook up the PCM to my laptop to perform this delete? If so, can you send me a link and/or any advice?

 

Not really...
These PCMs used a P.R.O.M. Module (Programmable Read Only Memory) that would be similar today, as a SD-Card/ Micro SD-Card.
The P.R.O.M. Module gets removed, reprogrammed, and reinstalled.

Anyway, the Early VAT System is very basic...
With the resistance-value of the Ignition Key Resistor-Pellet, the VATS Connector to the Ignition Key Lock-Cylinder can be disconnected...
and a Resistor of approximate equal value can be installed into that Connector.

After that, the Starter Motor Enable Relay can be Jumped or better yet; permanently bypassed.

We have tons of Threads on this Topic already on the Forum, that you can search and read.

 

I think he has an LS swap. Is there a free software that will let him turn off VATS in the PCM?

https://www.thirdgen.org/forums/elec...pass-vats.html

 

Correct...this is n LS swap so I have the 2002 PCM (Serial #...0041). I do have a Moates APU1 AutoProm package, but I believe that will only work on the 3rd gen PCMs. Looking for free software to delete the VATS or an "entry level" tuner (HP Tuner?) that I could purchase.

 

Just checking in looking for free software to delete the VATS or an "entry level" tuner that I could purchase. Would appreciate a make/model or hyperlink. Again, this is n LS swap so I have the 2002 PCM (Serial #...0041). I do have a Moates APU1 AutoProm package, but I believe that will only work on the 3rd gen PCMs. The Starter Motor Enable Relay is already jumped. I did read your entire thread QwkTrip & vorteciroc...great stuff there! Thank you all again!

 

I am not familiar with any Free Products...

HPTuners would be fine for this,

 

Hi again...ok just getting back to this crank, no start issue. All wired correctly yet still experiencing the voltage drop on all fuel injector signal wires. I have great fuel pressure at the rails, and plugs, wires, coils & injectors are all new. I did replace the PCM with one that supposedly has a deleted VATS. Is there any other security computer or module that needs disconnecting or requires to be tuned out? As a reminder, starter relay is also bypassed as shown below. Thank you!

 

Have the Fuel Injectors ever been looked at?

General Condition, Take an Impedance Measurement, Make certain that they are not clogged up with junk?

 

As mentioned in my post above, (among other things), the injectors are brand new. That said, I can't imagine they are clogged. Also, that should have nothing to do with a voltage drop on the injector wires since when testing the signal with the noid light, I disconnect the harness from the injectors too. I am questioning if the VATS was truly disabled. This situation is so symptomatic of VATS. Even though the PCM I purchased "supposedly" has VATS deleted, I am goin to have that doubled checked for accuracy. Any other thoughts? Thank you!