Hey Everyone.

Ive got a truck harness that im trying to work into my swap with my LM7, however, with the LS1 intake, & stuff, its making the truck harness hard to use.

Can i use my '03 Ecm with a 99-02 Harness?

Thanks!

 

It will take a little repinning to the best of my knowledge. Other than that you will have to change the pcm connector plastic wire retainers. The 03 up use blue and green and the 99-02 harness will use red and blue. The 03 up pcm also uses ETC. Are you going ETC or cable throttle. If going ETC route you will have to add the necessary wires for the throttle body and TAC module to the 99-02 harness. Not any big deal just a little time and planning. You need to put a 02 pcm harness connector schematic and the 03 truck side by side and then go pin by pin to make sure what wires need to be moved are done so correctly.