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LS short box · 06-01-2023, 05:16 PM

For most LS swaps the LS harness is totally separate from the C10 electrical harness. From the Autowire harness you need 12 volt constant and 12 volt switched hot in start/run going to the LS ECM. Its really important to have really solid grounds with a LS swap. Engine to the frame. LS harness grounds to the back of the cylinder heads. Frame to the battery. You can build a LS harness from a salvaged vehicle. I don't do that. I buy the harness and ECM (and TCM) if needed from one supplier with a base tune.

06-01-2023, 05:16 PM	#2
LS short box Registered User Join Date: Jun 2015 Location: Carlos MN Posts: 1,943	Re: Original dash harness Question For most LS swaps the LS harness is totally separate from the C10 electrical harness. From the Autowire harness you need 12 volt constant and 12 volt switched hot in start/run going to the LS ECM. Its really important to have really solid grounds with a LS swap. Engine to the frame. LS harness grounds to the back of the cylinder heads. Frame to the battery. You can build a LS harness from a salvaged vehicle. I don't do that. I buy the harness and ECM (and TCM) if needed from one supplier with a base tune.