HU Harness question. Trying to avoid splicing.
#1
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I'm going to be installing an aftermarket HU here soon and was wondering about the harness.
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
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
#3
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Your question is a little confusing so bear with me if my answer covers things you already know.
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.
#4
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Your question is a little confusing so bear with me if my answer covers things you already know.
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.
#6
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Thank you, that was EXTREMELY helpful.
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.
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Chris
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#8
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And the nice thing about the adapter harness is that it uses industry standard wire colors so you don't have to look up what color wire is for each function. Just connect the adapter harness to the aftermarket HU wires color for color (red to red, orange to orange, etc.) and the adapter harness takes care the circuit matching.
#9
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Here's a dumb one, but is that the correct harness to use for Monsoon systems to swap in an aftermarket head unit while maintaining the use of the monsoon amp?
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That's what i was thinking, it probably just actually uses the blue remote wire to actually turn on the amp. But then the actual speaker wires at the head unit must be dummy wires, since you can't have power coming form the head unit and the amp for the speakers?
#12
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No, the Monsoon amp doesn't use a remote turn on wire. It uses signal sensing on the input side to turn on when the head unit starts sending audio signal. And no, none of the wires at the HU are "dummy wires". The normal speaker-level output from the HU is the input to the Monsoon amp. It doesn't use pre-amp (line-level) input like most aftermarket amps do.
The Monsoon FAQ sticky at the top of the section has lots more information.
The Monsoon FAQ sticky at the top of the section has lots more information.