Electrical Problems After GT Swap

[Wolf Mxbee]

I swapped my 05 V6 Mustang with a V8, last night I tried to connect the battery and didn’t get any lights on or anything besides my gauges but only my security and abs light, with the key and lights on with the switch, nothing would work. I Disconnect and reconnected the battery quickly and all of a sudden it jumped the car and lights turned on right away and my gauges are fully lit now so I knew I had power so I tried to hook up my SCT Pats removed tune and it popped up with a code 11020 “Unable to communicate” so I turned off the light switch and pull my key out and all of my lights on the dash and exterior are still on as if it was running when I never turned the key to the start position. It isn’t running yet but so far I have done is swapped the automatic V6 ecu for a manual V8 ecu, rewrapped all the wiring harness so I know there are no tears or ripped connections; however, my body harness is a 05 while my engine harness is an 07 and the C110 plugs are different so had to splice them together and get rid of the plug connection, have 3 wires left over on both but because the wiring diagram shows the 3 don’t match up with each other and I don’t think that’s why I’m having issues, I think maybe my PCM for my body control module?

 

[Juice]

For one thing, you should not need a pats delete tune. Pats is solely in the pcm and you can program keys using Forscan with usb elm327 adapter. (Bluetooth and wifi adapters suck for programming, good for diags)

Not communicating means one of two things: pcm is not powering up OR the can bus has an issue. Shorted, not connected, bad module on the bus etc.

Thats all I got, as you have a unique issue from the description.