Hey Guys,
I have an 07 LT which had a 2.2. I recently swapped the 2.2 with a 2.4 VVT out of another 07 LT. Using the donor I also replaced the engine wiring harness and ECM. there is a 10 pin plug in the engine bay, as far as I can tell it goes to the headlight switch inside the car, high and low beams, etc and maybe BCM as well..... I think..... anyway the new harness takes a 12 pin plug below the fuse box instead of the existing 10 pin. Can I modify this or do I need to find another harness? Thanks in advance for your expertise, I appreciate it!

 

Some pictures would help.

Does the 12 pin connector have wires in extra cavity or are they empty?

 

I got no idea why the headlight switch would have anything to do with the Engine wiring harness.

 

I was thinking the same thing. They are on a separate "chunk" of the fuse panel. Are the 07's similar in that the panel is modular?

On the 08SS the fuse panel comes apart in 5 pieces, each associated with a different harness. I'm wondering how your 2.4 wiring harness would have anything to do with headlights or the bcm.


@KJT from what it sounds like you are referring to the harness plug (module) this is your primary source for 12v to sensors and whatnot. If your new harness is 12 pin, your going to have to see what is using those 2 pins. You may be able to modify it, but I think I'd trace those 2 out. If that isn't an option, I'd try and get the correct topside module from a 2.4 that has the 12 pin that fits your harness.

I'd stick with the harness that came with the motor, and figure out how to make it work. Take some pics and post them up. I LOVE electrical nightmares. Let's figure it out.

 

I don't know if this matters in this case but I though I would throw it out there.

The under hood harness is different in a panel from a standard window car. There are a set of extra relays next to the under hood fuse box for the electric door poppers on the panel.