So confused by my radio wiring...
09-16-2007, 01:30 PM
#1
Thread Starter
Join Date: 09-16-2007
Location: Dearborn, MI
Posts: 8
So confused by my radio wiring...
I just picked up a used 2006 LT that has an aftermarket Head Unit installed. I think the previous owner pulled out a few "extras" before they traded it in, but they say it "was working" when they traded it in. Looking at the wiring, I'm not sure about that.
The HU seems to have both pre-amp and speaker level outputs. The part that confuses me is that the speaker level outputs are connected to the HHR harness, and I have the Pioneer 7 speaker system which I understand has an amp! (Though I have not yet disassembled all the trim in the back to see what wiring changes might have happened there.) I'm kind of afraid that they might have mixed levels up and burned out something.
I have checked all the wiring diagrams I can find and done a bit of reading these forums and using Google to find information. From that research I have developed the following plan:
Keep the aftermarket HU (the pre-amp outputs seem to work, though I have yet to verify that the speaker level outputs work).
Figure out what might have been changed back by the subwoofer.
Restore the HHR radio harness to stock (they wired straight into the harness, yuck!).
Get a GMOS-LAN-04 and use it to connect the aftermarket HU (I'd like the chimes and On-Star to work - even if I think the service is too expensive).
-----
Now for the questions:
On the wiring diagrams I see the audio lines identified as "low level" - this is pre-amp level, right?
I would assume that a system with an amp (e.g. the Pioneer 7 speaker system) would want pre-amp levels from the HU, where one without an amp would need speaker level from the HU. However I found a post on this site that said the OEM radio is the same in both situations ( https://www.chevyhhr.net/forums/audio-video-17/difference-radios-7372/ ), what am I missing?
On a wiring diagram for the radio I see a line marked "remote radio control signal". If it is needed, I hope the GMOS-LAN-04 will take care of it, but what is it?
If I decide to chuck it all and go back to the factory radio (not really likely), what radio do I need to get and was other issues might I run encounter (recoding for VIN, etc.)?
All help will be greatly appreciated.
The HU seems to have both pre-amp and speaker level outputs. The part that confuses me is that the speaker level outputs are connected to the HHR harness, and I have the Pioneer 7 speaker system which I understand has an amp! (Though I have not yet disassembled all the trim in the back to see what wiring changes might have happened there.) I'm kind of afraid that they might have mixed levels up and burned out something.
I have checked all the wiring diagrams I can find and done a bit of reading these forums and using Google to find information. From that research I have developed the following plan:
Keep the aftermarket HU (the pre-amp outputs seem to work, though I have yet to verify that the speaker level outputs work).
Figure out what might have been changed back by the subwoofer.
Restore the HHR radio harness to stock (they wired straight into the harness, yuck!).
Get a GMOS-LAN-04 and use it to connect the aftermarket HU (I'd like the chimes and On-Star to work - even if I think the service is too expensive).
-----
Now for the questions:
On the wiring diagrams I see the audio lines identified as "low level" - this is pre-amp level, right?
I would assume that a system with an amp (e.g. the Pioneer 7 speaker system) would want pre-amp levels from the HU, where one without an amp would need speaker level from the HU. However I found a post on this site that said the OEM radio is the same in both situations ( https://www.chevyhhr.net/forums/audio-video-17/difference-radios-7372/ ), what am I missing?
On a wiring diagram for the radio I see a line marked "remote radio control signal". If it is needed, I hope the GMOS-LAN-04 will take care of it, but what is it?
If I decide to chuck it all and go back to the factory radio (not really likely), what radio do I need to get and was other issues might I run encounter (recoding for VIN, etc.)?
All help will be greatly appreciated.
09-16-2007, 01:37 PM
#2
Senior Member
Join Date: 04-30-2006
Location: Maryland Heights, MO
Posts: 9,149
OUCH!!!
Good luck getting this all straightened out.
About the only thing I can tell you for sure is that if you do decide to go back to stock, I wouldn't, you will have to have the car "flashed" to set the vin like you suspected.
Good luck getting this all straightened out.
About the only thing I can tell you for sure is that if you do decide to go back to stock, I wouldn't, you will have to have the car "flashed" to set the vin like you suspected.
09-16-2007, 05:03 PM
#3
Banned
Join Date: 10-24-2006
Location: The Show-Me State
Posts: 1,761
Um, what makes you think something is burned out? Are all the speakers not working or something?
The stock subwoofer has an independent amp that takes the signal from the left rear speaker. It doesn't use a line-level signal because the stock head unit doesn't have any line outs. I wouldn't worry too much about the factory signals. Your turn signals and all warnings flash on the DIC, so why worry?
You'll probably spend waaaay more restoring the wiring than it's worth. Enjoy the aftermarket HU and buy some new speakers to match it.
The stock subwoofer has an independent amp that takes the signal from the left rear speaker. It doesn't use a line-level signal because the stock head unit doesn't have any line outs. I wouldn't worry too much about the factory signals. Your turn signals and all warnings flash on the DIC, so why worry?
You'll probably spend waaaay more restoring the wiring than it's worth. Enjoy the aftermarket HU and buy some new speakers to match it.
09-16-2007, 08:55 PM
#4
Thread Starter
Join Date: 09-16-2007
Location: Dearborn, MI
Posts: 8
There is no sound out the speakers, except for a slight pop when the HU is turned off. Others may disagree, but I feel that factory features should be working, even if I don't need them. Some day I might want to get rid of this car (say, to ultimately get an SS), and I would rather have the OnStar and chimes working now than needing to fix things then. I only mention the subwoofer because I believe the amp (for all of the speakers) is mounted there. I don't care specifically about driving the subwoofer, I just wanted to know about the signal levels in general because the wiring I'm looking at doesn't make sense (to me). Besides, the HU may be bad, or I might decide later to put in a HU of my own choice, so I would like the factory wiring to be intact.
I think I got a very good deal on the car, and part of that is because the state of the audio system. I can afford to spend a little bit to get things right - besides I can do a fair amount myself (contrary to what others may believe, I do have some degree of a clue).
I think I got a very good deal on the car, and part of that is because the state of the audio system. I can afford to spend a little bit to get things right - besides I can do a fair amount myself (contrary to what others may believe, I do have some degree of a clue).
09-16-2007, 10:58 PM
#5
Banned
Join Date: 10-24-2006
Location: The Show-Me State
Posts: 1,761
The amp in the back is for the subwoofer only. It does not amplify the other six speakers at all. That amp receives its signal from the rear left speaker output--it is not a line-driven amp.
Also, is the car actually equipped with the OnStar system? Does it have the special buttons on the mirror? If not, it doesn't have OnStar.
Sounds to me more like the new HU was wired up wrong. Even if the amp in the back was blown it'd only affect the sub, the rest of the system would work fine. Check the speaker wiring and make sure he didn't wire it up backwards. It could be a bad HU he threw in there as a swap for one he's selling or installing in another car.
Like I said, you're going to have to spend some $$$$ if you want to go back to stock and even if you had to have a stereo shop sort it out and install a new aftermarket HU, I think that's probably going to be cheaper than hunting down a replacement factory wiring harness, factory HU, and getting someone qualified (dealer techs) to restore it all. Those factory harnesses ain't cheap at all.
Also, is the car actually equipped with the OnStar system? Does it have the special buttons on the mirror? If not, it doesn't have OnStar.
Sounds to me more like the new HU was wired up wrong. Even if the amp in the back was blown it'd only affect the sub, the rest of the system would work fine. Check the speaker wiring and make sure he didn't wire it up backwards. It could be a bad HU he threw in there as a swap for one he's selling or installing in another car.
Like I said, you're going to have to spend some $$$$ if you want to go back to stock and even if you had to have a stereo shop sort it out and install a new aftermarket HU, I think that's probably going to be cheaper than hunting down a replacement factory wiring harness, factory HU, and getting someone qualified (dealer techs) to restore it all. Those factory harnesses ain't cheap at all.
09-17-2007, 07:58 AM
#6
Thread Starter
Join Date: 09-16-2007
Location: Dearborn, MI
Posts: 8
I appreciate the feedback, but it doesn’t really fill in the blanks for my missing info, and it certainly doesn’t credit me with having any clue.
It most definitely has OnStar!
The wiring diagram I have seen shows all the channels going to an amp and then going to the speakers. Metra sells adapters for a HHR with an amplified system (GMOS-LAN-04) as well as for a HHR without (GMOS-LAN-03). So it would appear that, in the different levels of HHR audio options, some seem to have an amp that is more than just for the subwoofer.
As you can see, I feel that I need to understand the original wiring before I can start to figure out what is wrong with my current installation. Of course I’m missing some information and in other cases I’m seeing seemingly contradictory information. If you have specific details that would fill in the blanks or clear up the contradictions, that would be very helpful.
It most definitely has OnStar!
The wiring diagram I have seen shows all the channels going to an amp and then going to the speakers. Metra sells adapters for a HHR with an amplified system (GMOS-LAN-04) as well as for a HHR without (GMOS-LAN-03). So it would appear that, in the different levels of HHR audio options, some seem to have an amp that is more than just for the subwoofer.
As you can see, I feel that I need to understand the original wiring before I can start to figure out what is wrong with my current installation. Of course I’m missing some information and in other cases I’m seeing seemingly contradictory information. If you have specific details that would fill in the blanks or clear up the contradictions, that would be very helpful.
09-17-2007, 08:18 AM
#7
Senior Member
Join Date: 08-18-2006
Location: Hatboro, PA
Posts: 1,036
Try this ...
I don't know which one will look better...They are both the same.
https://www.chevyhhr.net/gallery/fil...6HHRSTEREO.gif
https://www.chevyhhr.net/gallery/fil...6HHRSTEREO.jpg
I don't know which one will look better...They are both the same.
https://www.chevyhhr.net/gallery/fil...6HHRSTEREO.gif
https://www.chevyhhr.net/gallery/fil...6HHRSTEREO.jpg
Last edited by GCarp; 09-17-2007 at 08:25 AM. Reason: changed to links from attachments
09-17-2007, 08:43 AM
#8
Senior Member
Join Date: 07-25-2006
Location: Enid, Oklahoma
Posts: 1,198
To start, I can't answer all your questions, but Crafty seems to be right in most of what he said, even if he did come off rude to you..
It sounds to me like the installer of the system wired it up backwards, hence your speakers not working.
I don't think any stock audio systems in the HHRs have separate amps running speakers other than the 7-speaker premium set-up, which has one external amp running the subwoofer. I could be wrong, but I'm pretty sure on this one. As for the HUs for the Premium and Standard, I don't know what the difference is in them, sorry.
The remote wire is, and I am not really sure on this one, for the steering wheel controls??
You might try a couple searches on here for "remote wire." I did and a lot of threads came up, but I can't seem to find my way around not wanting to sift through all that 
Good luck with it, though!
It sounds to me like the installer of the system wired it up backwards, hence your speakers not working.
I don't think any stock audio systems in the HHRs have separate amps running speakers other than the 7-speaker premium set-up, which has one external amp running the subwoofer. I could be wrong, but I'm pretty sure on this one. As for the HUs for the Premium and Standard, I don't know what the difference is in them, sorry.
The remote wire is, and I am not really sure on this one, for the steering wheel controls??
You might try a couple searches on here for "remote wire." I did and a lot of threads came up, but I can't seem to find my way around not wanting to sift through all that Good luck with it, though!
09-17-2007, 09:29 AM
#9
Senior Member
Join Date: 02-27-2006
Location: NC
Posts: 1,198
any chance they tapped into the wrong set of wires for the speakers (meaning the input end of the speaker wire to the amp) ? the four speakers wires(doors) run to the back and do go into the amp then run to the front of the car again, if they tapped in to the ones at the radio end then cut a power or remote wire goin to the amp you wouldnt be getting sound?
disclaimer; crowbar is and never was a stereo installer its just a thought, i did put my system in this weekend so im familiar with the wires,
disclaimer; crowbar is and never was a stereo installer its just a thought, i did put my system in this weekend so im familiar with the wires,