Need C4 Head Unit and Speaker Install Help!!
Thread Starter
Intermediate
Joined: Apr 2009
Posts: 27
Likes: 0
From: Wichita Kansas
Need C4 Head Unit and Speaker Install Help!!
Hello All,
After a long day of making sure I had all of my speakers fitted flush, make sure they were secure in their enclosures, running all of my speaker wires and pulling out the dash I ran into a problem. I can't figure out how to rewire this thing. I bought an adapter but soon found out that it did not fit. After visiting numerous car audio stores, best buy, walmart and other stores, I found out that they do not have the adapter I need in stock. After this disappointment I decided to just try to use the harness that was attached to the existing Bose head unit. I cut it and while preparing to attach the wires together I noticed that none of the wires back there fit what I was reading in the wiring diagrams. I have some strange harness in the back of my Bose head unit that has a 9-pin connector and a 7-pin connector. I have not been able to find any place that covers this.
To make a long story short, I am looking to you guys and gals for the answers. I have attached some pictures of the harness that the Bose harness was attached to, another picture of the other connector and a picture of all the junk behind my drivers seat in the cubby hole (I'm assuming this is the "brain" I keep hearing about but feel free to let me know if it isn't so I can start looking around in the passenger dash area). If any of you have encountered this harness type before and have found a way to wire it I would gladly appreciate your help. I would prefer not to hand my car over to the local audio shops so they can charge me an arm and a leg for something I could have easily found out on my own.
After a long day of making sure I had all of my speakers fitted flush, make sure they were secure in their enclosures, running all of my speaker wires and pulling out the dash I ran into a problem. I can't figure out how to rewire this thing. I bought an adapter but soon found out that it did not fit. After visiting numerous car audio stores, best buy, walmart and other stores, I found out that they do not have the adapter I need in stock. After this disappointment I decided to just try to use the harness that was attached to the existing Bose head unit. I cut it and while preparing to attach the wires together I noticed that none of the wires back there fit what I was reading in the wiring diagrams. I have some strange harness in the back of my Bose head unit that has a 9-pin connector and a 7-pin connector. I have not been able to find any place that covers this.
To make a long story short, I am looking to you guys and gals for the answers. I have attached some pictures of the harness that the Bose harness was attached to, another picture of the other connector and a picture of all the junk behind my drivers seat in the cubby hole (I'm assuming this is the "brain" I keep hearing about but feel free to let me know if it isn't so I can start looking around in the passenger dash area). If any of you have encountered this harness type before and have found a way to wire it I would gladly appreciate your help. I would prefer not to hand my car over to the local audio shops so they can charge me an arm and a leg for something I could have easily found out on my own.
Thread Starter
Intermediate
Joined: Apr 2009
Posts: 27
Likes: 0
From: Wichita Kansas
Ok. After reading through some of the posts I found here
https://www.corvetteforum.com/c4-general-discussion/2058190-96-full-stereo-re-do-part-ii-no-56k.html?styleid=140
I realized that I am an idiot and that I must find this cdm crap if I want to get anywhere. Any advice is still helpful so feel free to post but I am going to get some sleep o I can tackle this pain in the *** in the morning.
https://www.corvetteforum.com/c4-general-discussion/2058190-96-full-stereo-re-do-part-ii-no-56k.html?styleid=140
I realized that I am an idiot and that I must find this cdm crap if I want to get anywhere. Any advice is still helpful so feel free to post but I am going to get some sleep o I can tackle this pain in the *** in the morning.
Thread Starter
Intermediate
Joined: Apr 2009
Posts: 27
Likes: 0
From: Wichita Kansas
Hello All,
After finally getting my head unit and speakers installed I thought I'd give some helpful hints to aide you in your project. While doing my research I realized that while there is plenty of information on how to install a head unit and speakers in a C4, there aren't any specific guides on how to do it in a 1990 corvette. I wanted to put this up so that maybe the next persons project can be a little smoother than my own. I did this install on a 1990 C4 Corvette Coupe with a Delco-Bose Gold head unit. I hope someone gets some use out of this.
-------------------------------------------------------------------------
The Equipment I Used
-------------------------------------------------------------------------
- Head Unit = (I used a single din JVC unit with aux/bluetooth/usb - Not sure what the make and model are but I will update as soon as I check)
- Rear Speakers = (I used two 6.5 inch kenwood speakers. They fit into the stock enclosures perfectly and matched up with all of the holes)
- Front Speakers = (I used two 4 inch kenwood speakers. There was a bit of a gap in the fit so it required a bit of wiggling to make it where there weren't any gaps. A problem I ran into while installing these speakers were that they had 4 mounting holes while the stock enclosures only had 3 mounting holes. I had to bend a few things to make it fit but they sit in nicely now)
- Wiring Harness = (I used a Metra Mini Connecter for select GM vehicles. It had all of the wires I needed and matched up perfectly with the 3 plugs connected to the CDM unit)
- Dash Kit = (I am not entirely sure which dash kit I used but I bought it from a car audio installer and it was made for certain models (90 to 93. It fit and works great but it not much to look at)
- Wiring = (I used 14 guage wiring. Very small and easy to move around under the carpet)
- Tools = (Wire Crimper/Splicer/Cutter - Electrical Tape - Socket Set - Flathead Screwdriver - Phillipshead Screwdriver)
-------------------------------------------------------------------------
The Steps I Followed
-------------------------------------------------------------------------
(((Head Unit)))
- remove front of center console
- remove vents above heat/ac/stereo area.
- remove front of heat/ac/stereo area.
- remove head unit.
(((Rear Speakers)))
- remove the speaker covers.
- remove the speaker enclosures.
- remove the speakers from the enclosure.
- remove the amps and the stock wiring from the enclosure.
- install the new speakers into the enclosure.
- install the enclosures back in place.
(((Front Speakers)))
- remove the pilar panels (Just to the side of the seat).
- remove the side panels (just below the pilar panel along the door sill).
- remove the speaker enclosures.
- remove the amps and the stock wiring from the enclosure.
- install new speakers into the enclosure.
- install the enclosures back in place.
(((Wiring)))
- run wires from the head unit area and connect them to the front speakers.
- run wires from the head unit area and connect them to the rear speakers.
- run wires from the head unit area to the CDM unit location (Under the dash on the passengers side).
- locate the CDM unit and disconnect the three plugs on the right of it (the plugs should be located slightly under and behind the fuse box on the passengers side. If you want to use your radio antenna you will need to pull this unit out to access the wire).
- connect the wiring harness adapter to the three plugs pulled from the CDM unit.
- run the from the wiring harness adapter to the head unit wiring harness and match them according to your specific head units colors.
- connect the wires from your front speakers to the head unit wiring harness.
- connect the wires from your rear speakers to the head unit wiring harness.
(((Finishing Up)))
- connect your battery to test your system to ensure all the speakers and the head unit are working properly (Once you confirm all is working disconnect the battery again).
- install your rear speaker covers.
- install the side panels.
- install the side pilar panels.
- install the dash kit.
- install the head unit into the dash kit.
- install the front of the heat/ac/stereo area.
- install the vents above the heat/ac/stereo area.
- test your head unit/speakers.
-------------------------------------------------------------------------
Tips
-------------------------------------------------------------------------
- Take your time on the install to ensure the best quality.
- Check all of your equipment before the install to be sure that you have what fits and works in your vehicle.
- Make sure you take all possible safety precautions before starting.
- Be careful with your wiring. A few mixed up wires could possibly cause harm to your hardware.
- Be sure you take breaks while installing.
- Use this forum as much as you can. The people on this forum are very helpful. There are tons of people that have done this before you so they can help you with any questions or problems you may run into.
- For help locating some of the things I mentioned or getting certain items taken apart visit http://www.carstereoremoval.com/. It was very helpful during my install and I am sure it will be helpful during yours.
- Plan for the future. If you are going to eventually add amps or a sub, plan for it now. Run the wires if you have them. Pick your locations. This is the best way to make sure you aren't doing the same job twice.
After finally getting my head unit and speakers installed I thought I'd give some helpful hints to aide you in your project. While doing my research I realized that while there is plenty of information on how to install a head unit and speakers in a C4, there aren't any specific guides on how to do it in a 1990 corvette. I wanted to put this up so that maybe the next persons project can be a little smoother than my own. I did this install on a 1990 C4 Corvette Coupe with a Delco-Bose Gold head unit. I hope someone gets some use out of this.
-------------------------------------------------------------------------
The Equipment I Used
-------------------------------------------------------------------------
- Head Unit = (I used a single din JVC unit with aux/bluetooth/usb - Not sure what the make and model are but I will update as soon as I check)
- Rear Speakers = (I used two 6.5 inch kenwood speakers. They fit into the stock enclosures perfectly and matched up with all of the holes)
- Front Speakers = (I used two 4 inch kenwood speakers. There was a bit of a gap in the fit so it required a bit of wiggling to make it where there weren't any gaps. A problem I ran into while installing these speakers were that they had 4 mounting holes while the stock enclosures only had 3 mounting holes. I had to bend a few things to make it fit but they sit in nicely now)
- Wiring Harness = (I used a Metra Mini Connecter for select GM vehicles. It had all of the wires I needed and matched up perfectly with the 3 plugs connected to the CDM unit)
- Dash Kit = (I am not entirely sure which dash kit I used but I bought it from a car audio installer and it was made for certain models (90 to 93. It fit and works great but it not much to look at)
- Wiring = (I used 14 guage wiring. Very small and easy to move around under the carpet)
- Tools = (Wire Crimper/Splicer/Cutter - Electrical Tape - Socket Set - Flathead Screwdriver - Phillipshead Screwdriver)
-------------------------------------------------------------------------
The Steps I Followed
-------------------------------------------------------------------------
(((Head Unit)))
- remove front of center console
- remove vents above heat/ac/stereo area.
- remove front of heat/ac/stereo area.
- remove head unit.
(((Rear Speakers)))
- remove the speaker covers.
- remove the speaker enclosures.
- remove the speakers from the enclosure.
- remove the amps and the stock wiring from the enclosure.
- install the new speakers into the enclosure.
- install the enclosures back in place.
(((Front Speakers)))
- remove the pilar panels (Just to the side of the seat).
- remove the side panels (just below the pilar panel along the door sill).
- remove the speaker enclosures.
- remove the amps and the stock wiring from the enclosure.
- install new speakers into the enclosure.
- install the enclosures back in place.
(((Wiring)))
- run wires from the head unit area and connect them to the front speakers.
- run wires from the head unit area and connect them to the rear speakers.
- run wires from the head unit area to the CDM unit location (Under the dash on the passengers side).
- locate the CDM unit and disconnect the three plugs on the right of it (the plugs should be located slightly under and behind the fuse box on the passengers side. If you want to use your radio antenna you will need to pull this unit out to access the wire).
- connect the wiring harness adapter to the three plugs pulled from the CDM unit.
- run the from the wiring harness adapter to the head unit wiring harness and match them according to your specific head units colors.
- connect the wires from your front speakers to the head unit wiring harness.
- connect the wires from your rear speakers to the head unit wiring harness.
(((Finishing Up)))
- connect your battery to test your system to ensure all the speakers and the head unit are working properly (Once you confirm all is working disconnect the battery again).
- install your rear speaker covers.
- install the side panels.
- install the side pilar panels.
- install the dash kit.
- install the head unit into the dash kit.
- install the front of the heat/ac/stereo area.
- install the vents above the heat/ac/stereo area.
- test your head unit/speakers.
-------------------------------------------------------------------------
Tips
-------------------------------------------------------------------------
- Take your time on the install to ensure the best quality.
- Check all of your equipment before the install to be sure that you have what fits and works in your vehicle.
- Make sure you take all possible safety precautions before starting.
- Be careful with your wiring. A few mixed up wires could possibly cause harm to your hardware.
- Be sure you take breaks while installing.
- Use this forum as much as you can. The people on this forum are very helpful. There are tons of people that have done this before you so they can help you with any questions or problems you may run into.
- For help locating some of the things I mentioned or getting certain items taken apart visit http://www.carstereoremoval.com/. It was very helpful during my install and I am sure it will be helpful during yours.
- Plan for the future. If you are going to eventually add amps or a sub, plan for it now. Run the wires if you have them. Pick your locations. This is the best way to make sure you aren't doing the same job twice.
