Using factory amp bypass harness I get no sound from tweeters

[DolphineasMcGee]

I have a 2003 Yukon with Bose (UQ7 w/o Y91). My bose amp died and I'd like to replace the head unit as well. I was reading here that there is a factory harness behind the climate control I could use instead of running all new wires. However, when using the harness, there's no sound from the tweeters. There are two pairs of wires running to the tweeters that have continuity to the corresponding pins on the amp, but no continuity to the woofer in the door with the same colored wires.

Where does the other pair of wires from the tweeter go?

Does anyone have any information on this "factory amp bypass harness", wiring, why it's there, etc?

Also, if I do end up running new wires is there a guide to removing the panels, dash, etc, for fishing wires? I'm kind of leery about just poking around with the airbag there.

Thanks

 

[Fless]

Moved you here from the 2021+ section.

 

[Doubeleive]

on my 00 the tweeters were ran off of the door speaker with a small filter soldered on the tweeter. so unless they changed something after 02 then it should be same and i have never seen any ran differently in the junkyard or anywhere else unless there was a aftermarket install.
I would take the door panel off and confirm

 

[Joseph Garcia]

^^^^^x2^^^^^

Call Crutchfield and discuss your issue. They should be able to recommend an interface module that will allow you to install 3rd party head unit and amp, while still connecting directly to the truck's existing audio wiring harness.

 

[Tonyrodz]

I have a 2003 Yukon with Bose (UQ7 w/o Y91). My bose amp died and I'd like to replace the head unit as well. I was reading here that there is a factory harness behind the climate control I could use instead of running all new wires. However, when using the harness, there's no sound from the tweeters. There are two pairs of wires running to the tweeters that have continuity to the corresponding pins on the amp, but no continuity to the woofer in the door with the same colored wires.

Where does the other pair of wires from the tweeter go?

Does anyone have any information on this "factory amp bypass harness", wiring, why it's there, etc?

Also, if I do end up running new wires is there a guide to removing the panels, dash, etc, for fishing wires? I'm kind of leery about just poking around with the airbag there.

Thanks

Are you talking about the tweeters in the A pillars? Or the ones in the doors?

 

[drakon543]

without the amp in place the tweeters and woofer are separated. you will likely need to buy crossovers to wire inline to separate the signal for the woofers and tweeters. the secondary harness behind the hvac is for the non bose models that wouldn't have tweeters so they wouldn't be tied in.

 

[DolphineasMcGee]

Are you talking about the tweeters in the A pillars? Or the ones in the doors?

The tweeters in the A Pillars. I think the harness behind the climate control is connected to a plug from the amp that also feeds the tweeters. If I connect the "bypass harness" the front and rear door speakers and the D Pillar twiddlers receive sound.

I ran wires from the woofers to the A Pillars to connect to the crossover for the tweeter. I think if I run the speaker outputs from my aftermarket head unit to the "bypass harness" I can at least reuse the wiring for the door speakers instead of running everything new.

 

[DolphineasMcGee]

I started a collection of information that might be useful to anyone experiencing these issues or trying to figure out the wiring. It's available here.

 

[DolphineasMcGee]

They talk about the bypass connector and the issue with the tweeters in the video in this post about another way to bypass the amp around 8:00.

 

[DolphineasMcGee]

I also found out that the orange wires in the "bypass connector" are required to be connected in order for the primary connector to have power.

I ended up cutting (because I couldn't get a single pin out of that blasted Metra connector) the speaker wires for the doors out of the connector and plugging it back in. This gave me radio power. I then connected the door speakers directly to the wires (they have standard GM wiring colors). I ran separate wires through the door from the woofers to the crossovers for the new A pillar speakers.