I recently got myself a 06 Equinox. It had an after market radio in it when I bought it but it was shot and wouldn't work. So I got another radio unit and I wired it all up with the previously installed harness but my rear sub isn't working? Im sure it's because I never wired up any "sub" +\- wires into the harness.

I've read that all the sound goes through a factory amp. So my Front L/R and rear L/R are spliced in and work fine. But how to I send audio signal from my aftermarket radio to the factory sub? Typically with an aftermarket amp I'd have a pair of RCAs running from the radio to the amp. But I'm not sure how these factory ones work.

Thanks for any help

 

Are you still using the factory amp? If so, then the sub should still be working if you wired it correctly since the factory amp powers all speakers and the subwoofer. If you bypassed the factory amp, then your regular speakers are probably being powered by the radio's built-in amp, but the sub can't work unless you feed the factory amp a signal to send to the factory sub OR you install an aftermarket amp and connect it to the factory sub.

 

Yeah that's sorta my issue. As I said the car came with an aftermarket radio in it. It was properly installed with a harness. So all speaker wire connections matched up. But.. There was no wire/input to the sub back there.

So I guess my question is.. How does the factory radio hook/output to the factory amp? Is there a single set of wires/RCAs that goto the factory amp and then the amp separates into each +/- for the speakers? The problem is I can't tell if the amp has been bypassed or not. Seems proper behind the deck.

 

Here's what I found as far as a wiring list. As you can see it doesn't list the sub wires/output anywhere.

2006 Chevrolet Equinox Car Stereo Radio Wiring Diagram
Car Radio Constant 12v+ Wire: Red/White
Car Radio Switched 12v+ Wire: The radio harness does not provide a switched power source. Run a wire to the fusebox for switched power. The accessory turn-on and amplifier turn-on are controlled by the class 2 serial network.
Car Radio Ground Wire: Black/White
Car Radio Illumination Wire: N/A
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger: N/A
Car Stereo Amp Trigger Wire: Pink
Car Stereo Amplifier Location: Under the driver side rear seat bottom cushion.
Front Speakers Size: N/A
Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Tan
Left Front Speaker Negative Wire (-): Gray
Right Front Speaker Positive Wire (+): Light Green
Right Front Speaker Negative Wire (-): Dark Green
Rear Speakers Size: N/A
Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Brown
Left Rear Speaker Negative Wire (-): Yellow
Right Rear Speaker Positive Wire (+): Dark Blue
Right Rear Speaker Negative Wire (-): Light Blue

 

The factory radio doesn't send a discrete subwoofer signal to the factory amp. That is why you don't see a sub output any listed anywhere for the radio. The factory amp internally sums the regular four channels coming from the radio into one signal then sends it to the subwoofer's amp channels (factory sub is dual voice coil). Looking at the radio installation won't tell you much of anything. You need to look at the connections at the factory amp and check for cut & spliced wires to tell if it has been bypassed. If it is not bypassed then you'll need to troubleshoot further as either the subwoofer output stage of the factory amp is bad or the factory sub is blown.

I've attached a wiring diagram to help you.

2006_Equinox_premium_sound_wiring_diagram.pdf