Head unit won't turn off...

[Denial-]

Working on putting in the first aftermarket head unit from the factory one, finding more issues than I should. I have 2 red wires coming from the car harness that's it, no yellow. There's a red and a yellow coming from the aftermarket harness, I've tried wiring the red to the red, yellow to the other red, and then switching the two, either way the head unit always has power with the key off etc. How should I wire this up so the head unit turns off when the keys turned off like normal? The factory one worked fine so I know it can be done somehow lol. I've attached some pics to show better what I'm talking about. Yes the two connections at the red and yellow wires are just temporary lol.
Thank you guys for the help, this is killing me and I haven't even gotten to the fun stuff yet...

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[Water Bear]

You can use your DMM and find a wire coming from the factory harness that's switched. Fork that wire to whatever your stereo needs.

 

[Denial-]

You can use your DMM and find a wire coming from the factory harness that's switched. Fork that wire to whatever your stereo needs.

Once I find that wire, which wire would I connect to it coming from the aftermarket harness, the yellow or the red? I have no idea why I have 2 reds coming from the factory harness, im assuming one has to be the yellow... I don't get why it won't work normal with whatever I try though.

 

[Water Bear]

Once I find that wire, which wire would I connect to it coming from the aftermarket harness, the yellow or the red? I have no idea why I have 2 reds coming from the factory harness, im assuming one has to be the yellow... I don't get why it won't work normal with whatever I try though.

Your head unit should have come with a manual which includes a wiring diagram. Given a choice between red and yellow I'd guess yellow is the remote turn on, but you should be able to find this information in a manual somewhere. Likewise your harness should have documentation somewhere - a website or a manual that came with it.

 

[Denial-]

Your head unit should have come with a manual which includes a wiring diagram. Given a choice between red and yellow I'd guess yellow is the remote turn on, but you should be able to find this information in a manual somewhere. Likewise your harness should have documentation somewhere - a website or a manual that came with it.

The aftermarket harness for the head unit has a separate turn on, the blue with white, and it also has a yellow and red, constant and switched, I wss asking in your opinion which of the two either the constant or switched should I connect, im assuming the switched but then I'm going to have the issue of the head unit not having power to keep my presets and other things if I don't connect the constant.

 

[Water Bear]

The aftermarket harness for the head unit has a separate turn on, the blue with white, and it also has a yellow and red, constant and switched, I wss asking in your opinion which of the two either the constant or switched should I connect, im assuming the switched but then I'm going to have the issue of the head unit not having power to keep my presets and other things if I don't connect the constant.

Not totally following, but you need both the 12v constant and the switched.

I'm suggesting that you connect potentially more than one wire coming out of the head unit into a single wire from the aftermarket harness (not to repeat what you already know).

 

[audiobaun 5,000+ posts]

Are you 100% certain that you bought the correct wiring harness for the vehicle?

 

[Denial-]

Are you 100% certain that you bought the correct wiring harness for the vehicle?

I actually wasn't for the longest time... I swore it wasn't because of stuff like this but it does plug in fine to the vehicle harness and I looked up other brands for my year and make etc and they all look the same with the same pins in the same spots.
I have two solid red wires coming from the car harness my issue is I have a yellow and a red coming from the head unit and aftermarket harness so im trying to figure out how to wire the red and yellow into the two reds in the right way so the head unit actually turns off when the car is off. Sorry this is so confusing to explain.

 

[audiobaun 5,000+ posts]

It looks like to me.. In Pic 3 there is a red wire coming out of the Plug that is just cut and not attached, of which looks like it should go to the Red wire on the HU that you have attached to one of the Yellow wires that should be capped off with the other Yellow to Yellow to stay attached??

 

[audiobaun 5,000+ posts]

It looks like to me.. In Pic 3 there is a red wire coming out of the Plug that is just cut and not attached, of which looks like it should go to the Red wire on the HU that you have attached to one of the Yellow wires that should be capped off with the other Yellow to Yellow to stay attached??

Actually I can see it better when I Blow PIC #1 up. Check that cut off Red wire out of the harness with a DMM to see if you have 12v. Use Ground /Black on DMM to Black wire or find a bolt under dash to ground to in order to test with the Redon DMM to that Red cut off wire

 

[audiobaun 5,000+ posts]

Maybe someone other than me can verify.. But thats what I can tell from the pics that looks like could be your issue with constant 12v/ILLum.-YELLOW attached to 12v On/Off supply RED from Harness to HU/Radio

 

[Boominburban]

What's the year, make and model of vehicle? What was the oem system?

 

[Denial-]

What's the year, make and model of vehicle? What was the oem system?

2007 jeep grand cherokee no fancy bose or optional amp or anything else like that.

Audiobaun I was waiting for you to see the thread I had high hopes you or winky would get it lol. As to what you're asking, the one red wire is capped off im gonna try to explain this the best I can bc its confusing as ****. I only have 2 red wires coming from the cars factory harness, those are in the far right top and bottom. I have 2 yellow and 1 red coming from the aftermarket harness I bought that plugs into the cars harness. The 2 yellow are in the right spot the far right but then the red goes to nothing on the other side of the factory car harness so I just didn't use that wire which is why It's just capped.
I feel like at this point I need to test the two red wires I have coming straight from the cat harness to find which one is switched and which one is a constant right? I'd do this by just connecting the dmm negative to the ground wire and the positive to either of those reds and turn the key on and off and see which gives me switched voltage and then wire the red to the other one right? I did already just try to reverse how I had it wired up in the pictures and still had the same problem though.

 

[Water Bear]

2007 jeep grand cherokee no fancy bose or optional amp or anything else like that.

Audiobaun I was waiting for you to see the thread I had high hopes you or winky would get it lol. As to what you're asking, the one red wire is capped off im gonna try to explain this the best I can bc its confusing as ****. I only have 2 red wires coming from the cars factory harness, those are in the far right top and bottom. I have 2 yellow and 1 red coming from the aftermarket harness I bought that plugs into the cars harness. The 2 yellow are in the right spot the far right but then the red goes to nothing on the other side of the factory car harness so I just didn't use that wire which is why It's just capped.
I feel like at this point I need to test the two red wires I have coming straight from the cat harness to find which one is switched and which one is a constant right? I'd do this by just connecting the dmm negative to the ground wire and the positive to either of those reds and turn the key on and off and see which gives me switched voltage and then wire the red to the other one right? I did already just try to reverse how I had it wired up in the pictures and still had the same problem though.

Yep, that is how you test it. A switched wire is 0V relative to ground with the key off, 12V key on.

 

[Denial-]

Yep, that is how you test it. A switched wire is 0V relative to ground with the key off, 12V key on.

And once i find the switched wire I'm wiring the red accessory to the switched or the yellow constant to it?
And obviously the other wire goes to the other red im assuming right?