HU Harness question. Trying to avoid splicing.
I know I will need to get the harness (PN 70-1858 GM21 pin) and splice this into the stock harness using caps or soldering it, but I was wondering if I could just get another stock harness plug (pn 71-1858) and put the wires from 70-1858 into it. So it would be more like an extension with the correct aftermarket plug going into the new HU.
Hope what I'm saying makes sense. Just going for a cleaner look, but not sure if I will need a specific female end, or if it's interchangeable.
Has anyone done this before?
In searching, Circuit City used to make these but doesn't any longer.
Thanks.
-Matt
The harness you got does not splice into the factory wiring. It is designed to connect to the aftermarket head unit wiring so that the new HU will plug into the factory connector without modification. That allows you to go back to stock or update to a different HU in the future by just unplugging the harness.
Circuit City used to produce adapter harnesses that did the same job but also had connectors for each major brand of aftermarket head unit. That way both ends of the adapter harness would be plug-and-play rather than having to manually connect wires at the HU end like the Metra 70-1858. Unfortunately, now that they are out of business, I don't know of anyone that supplies connectors for each of the aftermarket manufacturers other than the manufacturers themselves.
The 71-1858 is the plug that is already on the end of the factory harness. It is used to repair the factory harness when a previous owner has butchered it by splicing in an aftermarket HU (rather than using the 70-1858 adapter as they should). It is not necessary - or even useful - for an ordinary install.
The harness you got does not splice into the factory wiring. It is designed to connect to the aftermarket head unit wiring so that the new HU will plug into the factory connector without modification. That allows you to go back to stock or update to a different HU in the future by just unplugging the harness.
Circuit City used to produce adapter harnesses that did the same job but also had connectors for each major brand of aftermarket head unit. That way both ends of the adapter harness would be plug-and-play rather than having to manually connect wires at the HU end like the Metra 70-1858. Unfortunately, now that they are out of business, I don't know of anyone that supplies connectors for each of the aftermarket manufacturers other than the manufacturers themselves.
The 71-1858 is the plug that is already on the end of the factory harness. It is used to repair the factory harness when a previous owner has butchered it by splicing in an aftermarket HU (rather than using the 70-1858 adapter as they should). It is not necessary - or even useful - for an ordinary install.
I guess I was having a hard time putting it together in my mind without actually seeing it.
So what you're saying is, the headunit will come with some type of connection wiring, and the 70-1858 gets connected to that allowing the 70-1858 to plug right into the factory wiring? This will prevent me from having to modify the factory wiring in an event I want to return to the stock HU.
I guess once I see it, it will make sense.
Thanks.
I guess I was having a hard time putting it together in my mind without actually seeing it.
So what you're saying is, the headunit will come with some type of connection wiring, and the 70-1858 gets connected to that allowing the 70-1858 to plug right into the factory wiring? This will prevent me from having to modify the factory wiring in an event I want to return to the stock HU.
I guess once I see it, it will make sense.
Thanks.

Chris
That's what I was picturing after whitebird lead me to the water.
Perfect.
Thanks a lot guys, I have a clear idea now.
-Matt
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