So I'm trying to install a 2005 LS2/4L65e into my 81 C10. I was able to take the engine, trans, radiator, fans, underhood fuse box, pedal, and C1 ecm harness from this 69K mi car. So far it's going well, the PCM is out being tuned for VATS and a few other things right now so this is the best time to sort out the wiring.

I've been trying to figure out a few wires from the C1 connector.

1. Ignition 3 voltage circuit 300
2. Accessory voltage circuit 1843
3. crank voltage circuit 5
4. what wire do I need to hook up to the brake to turn the torque converter clutch off?
5. Do I need to hook up anything from connector 206 (white plug from ecm harness near gauge panel and TCM.)
6. Do I need to run the starter through the factory under hood fuse block and relay?
None of these would be problems if I could find some proper schematics but it seems even Alldata is lacking when it comes to these Holden GTO's.

There are a ton of diagrams on LS2 from a member in Australia that have been worth their weight in gold but they seem to be lacking a few connection points. Any help or direction would be appreciated. Pics to follow.

 

Here's some info on the C206 connector.

And another helpful thread.

Tipsy

 

Thanks for the reply.

For anyone else fighting this problem I have found this info:

1. Goes to the PIM and may not be necessary
2. Looks like these go to the ECM and TCM through C206 and into the interior fuse box via a micro relay. Not sure if these need a relay in my case or just IGN power. ??
3. Used to hook up the starter through the PCM but not necessary in a swap case when using the vehicle's existing wiring system.
4. Still looking into this one. Looks like pin 32 out of C1 is the turn off for the TCC but there may need to be one hooked up to energize the TCC that will turn off once brakes are applied then re apply once brakes are released. ??
5. Yes...IGN and B+ not to mention some brake switches and AC stuff goes through this.
6. As mentioned in 3. No, this is only necessary in it's stock application.

If anyone has any other info on this or disagrees with my findings, please chime in so I, or anyone else for that matter, gets this right and doesn't light a harness on fire...lol. Thanks. Alex.

 

Here is another good reference. It's based on an SSR harness but they are very similar to the GTO. In fact, there are several known errors in the GTO factory pinout information that don't seem to be replicated in the SSR info.

His pinout info is here.

Tipsy

 

1. You're correct. I didn't use any of those circuits when I swapped. I installed a Painless fuse block under the hood, and only used relays for a couple of things.

2. I don't know where on the harness(es) C206 is, and don't have the pin-out for circuit 1843 in front of me, but I made sure the PCM and TCM had all of their ACC, BAT+, and IGN inputs. There weren't many at all... handful.

3. Correct... I didn't use these circuits at all.

4. I can get you the pin-out and wire I used for TCC. I replaced the '69 single brake light switch with a dual-switch from a 3rd Gen, (Normally Open\Normally Closed) running the TCC signal thru it for the torque converter. But I believe you're correct on Pin 32. That's all I used.

5. Again, not sure what C206 is (my swap was from a '05 GTO), but if it's got IGN and BAT+ running thru it, definitely power it that way. I found this out the hard way when my trans was in limp-mode. I neglected to power it's BAT+.

6. Correct... no need. The starter can be powered the way it always has been from the factory.

Not only are some of the GTO diagrams messed up, but there are Corvette diagrams mixed in from different web sites, making it even harder to decypher. Wire colors and things do NOT match a 2005\2006 GTO. That second link that Tipsy posted is me.

EDIT: Going back and reading my posts over there from 2013, I still have no idea what C206 does, and don't remember using it or it's wiring at all during the swap. The only odd connector I needed to be concerned with was C101. It's VERY important. I have the feeling C206 is a connector I have tied back out of the way. I'll have to look at it and see if I used any of it's wiring.

 

There is a large firewall grommet on the stock harness. On the cabin side of the grommet is a large 26 pin white connector. It is the C206. Here are the pinouts of the C206.

Tipsy

 

Right, its vaguely familiar. Now that I'm home I'll pop the hood and see if I used it for anything. I kept all the wiring in the engine bay for the time being until I was sure I got everything, so it'll be easy to look at.

 

Thanks guys.

On the TCC deal... I have the availability of going back to the GTO I pulled the engine out of and getting the stop lamp switch. Do you think this is a better idea than trying to wire one up?

 

Ok I found this but am not sure if circuit 847 pin 38 needs to be powered at all times until I hit the brakes and power circuit 20 pin 32. Thoughts?

 

Sorry for the delay... I'm on the beach and totally forgot.

38 has nothing to do with the brakes or TCC other than the STOP lamps. I did not even wire it. I'm not using the GTO stop lamp switch so it's not needed.
My car still uses all of the factory wiring except the engine and trans harnesses.

Again, sorry I forgot before I left for the island so I don't have my folder in front of me. There's a couple diagrams around (here and elsewhere) showing how to wire a later-model Normally Open\Normally Closed brake light switch. It took a little ingenuity to replace the factory switch with the later-model one and mount it, but it fit and works fine.

One side is wired as it should be for YOUR cars brake lights from the factory, and the other side wired to the TCC signal from the computer to unlock the converter when you step on the brakes. It's just one wire and a ground to each side of the switch.

I definitely powered 32 thru a fuse.
I swear I'll break out my folder when I get back (if I decide to re-enter humanity) and show you what I did.

 

Awesome! Thanks sir.

 

I powered the ECM:
C1 - Pin 20 with B+ (constant 12v)
C1 - Pin 14 and 19 with IGN 12v
C1 - Pin 18 is ACC voltage

I don't find that diagram you show in my paperwork. I may have missed it. I know I said I powered Pin 32 but I'm wrong because it has to do with the stop lamp switch. I know I used most of the wires in C101 because they power the Coils\Injectors, and the automatic transmission. It also powers the A\C but I didn't use it.
C101 - Pin 2 red: Passenger side
C101 - Pin 3 lite green: Drivers side
C101 - Pin 5 pink\blue: Trans
C101 - Pin 4 black: Ground
C101 - Pin 6 dark green: A\C
C101 - Pin 1: Empty

One thing I don't remember how I wired was the VSS (vehicle speed signal) for the Dakota Digital controller for the speedometer. I'm sure I used a VSS signal from the ECM somehow.

The TCC signal(s) on the automatics TCM are Pins 1 and 25. I used Pin 25 (solenoid valve control) and wired it to the brake light switch.

I replaced the factory brake light switch with one from a 2000 Camaro\Firebird because that's what fit the best for me. Yours may vary. Not sure of the part number. As long as it works the way the one in the link shows, you're good.

This link shows the drawing\picture I went off of...and I didn't use a relay because I'm not using Cruise Control either:
https://ls1tech.com/forums/conversio...ng-please.html