This harness is standalone and is not intended to replace the OEM engine wiring.
Standalone harnesses are intended to run the designated engine and transmission only, generally when swapped into another vehicle.
Designed for use on any LS3 with throttle by wire from 2007 and up, this harness uses the factory ECM and TCM and will operate engines with or without variable valve timing (VVT) and active fuel management (displacement on demand or DOD).
This harness does not support flex fuel operation and will not work on GTO's.
Included with this harness is a 10-circuit weatherproof fuse block and mounting bracket, GM color coded wires with labels, and all the required terminals and connectors for easy installation.
This standard length harness allows four feet from the back of the intake manifold to where the fuse block and ECM mount, perfect for those that plan to mount these components under the dash or in the glove box.
This harness also requires the following mating parts: ECM #12597121 or #12612384; TCM #24234503; Accelerator pedal #25832864 or #25835421.
We recommend checking the online manual for the full list of required mating parts prior to ordering.