Id like to thank stealththx for making the Original FAQ Sticky
but with the new 07+ vehicles it became more confusing then it was worth. I retained some info but also added on but i still need to fill in part numbers and such so its still a work in progress.
1.) If I install an aftermarket head unit will I lose my Driver Information Center (DIC) or throw a check engine light (CEL)?
No, removing the factory radio does not affect anything related to the DIC since it is located in the dash not in the radio like the new G6 and Malibu and a properly installed aftermarket HU will not effect the computer.
2.) Now do I have to relocate the factory radio in order to maintain any factory functions. (Do I have to run a harness from the front of the car to the trunk and hide my factory radio?)
No. Even thou the Cobalt uses the new GM-LAN system in the vehicle unlike the previous generation of GM vehicles which used the Class 2 Databus which some of you might be familar with the harnesses now available will still work with the GM-LAN system.
3.) Also, will I lose the factory door chime with the installation of an aftermarket head unit on an 05-06?
No, the factory door chime is still retained since it is not connected to the radio in any way.
4.) What about an 07+?
The 07+ cobalts have the door chimes play thru the speakers stock... So when you remove the stock HU you loose them unless you get a expensive module to replicate the chimes called the GMOS-LAN harness.
5.) What Harness do i need for my 05-06?
Metra = 70-2103
Warning the Scosche, AI and Bluewave harnesses are for Saturn's... the plug will physiclly work but you will need to repin the speaker wires along with cut or remove the 2 red "jumpers". I dont recommend them but i have the part numbers listed.
Scosche = GM04B
American International = GM-4003
Bluewave = BW-H-GM20
6.) I have an 07+ and need a harness, which one do i get?
Listed below are the expensive "module" harnesses for the second option look at question 7
Metra= non pioneer = GMOS-LAN-03
pioneer = GMOS-LAN-04 *retains onstar*
Pac= C2R-GM11 *without onstar*
7.) Is there another solution other then the pricy gm lan harnesses for 07+ vehicles?
Yes you can buy the regular harness that will plug in but you will loose your door chimes.
Metra = 70-2104 (70-2202 should work as well but the 2104 is the best option)
American International =
8.) What antenna adapter do i need for my cobalt?
05-06 cobalts need the GM antenna adapter
Metra = 40-GM10
Scoshe = MDA1B
07+ Cobalt's need the Chrysler antenna adapter
Metra = 40-CR10
Scoshe = CRAB
9.) What about the Scoshe dash kit that has the screen on the bottom and claims to retain the factory DIC functions?
Its not necessary for the cobalt but it will work so if you really want it go for it. Part number is GM1593B
10.) So I'm not sure what exactly a DIN is or what size head units I can fit in the Cobalt
In a nutshell the DIN size refers to how big the opening is to fit a new head unit. The Cobalt has a big enough opening for a double din and currently the kits made for it are Single DIN, Double DIN, and dual Single DINs.
Single DIN kit number
Metra = 99-3302
Double DIN Kit Number
Metra = 95-3302
Dual Single DIN kit number
Metra = 95-3302 (ISO mount only)
11.) I really want a new head unit but I still want to use my steering wheel controls!
No problem. Check out these bad boys PAC Audio Steering Wheel Interfaces
12.) Now I have the XM option in my Cobalt and I want to get a new head unit but use that XM antenna up on my roof. How do I do this and do you recommend this?
Personally, I [stealththx] don't recommend this because it will be more of a hassle with various adapters and whatnot and you will not have a full function XM system. If you install a Pioneer DVD/Navigation system in your car it is able to receive XM NavTraffic information and with the factory antenna this is not possible. With XM NavTraffic service you can receive live traffic information, stock quotes, and more on your AVIC series head unit.
13.) I really want a DVD player and Navigation system so what do you recommend for me?
The Top three companies when it comes to high end head units or DVD units are Pioneer, Alpine and Eclipse
14.) Ok, I am installing a new head unit in my car and I can't find a switched acc wire for my remote turn on lead what do I do now?
The accessory for the radio is actually run by the GM-LAN system. You must find a switched accessory wire somewhere else like tapping into one in the fuse box. The best fuses to tap are the Sunroof fuse or Windshield wiper fuse.
15.) I have an 05-06 cobalt and i want the aux in like the newer 07+ radios. Can I just swap one of those head units in my car?
Quick answer is no... yes its been done by one person (SilverSS/SC) "All of the functions work . The only thing that was screwy was the radio controls and thats only because the 2007 steering controls do not have all the functions the 05-06 controls have. 2007's only have volume , seek/scan(up/down on CD tracks) and mute and all those function do work on my 05 steering wheel controls"
He also knew someone that worked at gm and had extensive knowledge of the tech 2 software... "Yea , tech2 was a bitch to get to read the radio that shouldnt have been there . From what I can remember ( my friend that worked at the dealer quit so I no longer have tech2 access ) , theres 3 different ways to do a vin relearn on a radio .....only 1 of them worked . The other 2 ways could see the radio , but it couldnt change the 07 vin assigned to the radio to my 05 vin so nothing would happen , the tech 2 would basically stuck on a loading info screen and stay there until u aborted the command ."
Heres the thread with more info on it
16.) I have an 07 oem radio with xm and the ipod and mp3 player in it.. is there any way i can buy the upgraded one with the 6 disc mp3 player in it?
Yes As long as its out of an 07+ vehicle all the connections are the same. If by chance you buy it used or from another member you will need to get the vin relearned via a dealership but other then that it would work.
17.) How do i and an amplifier and keep the stock radio?
You can either buy a Line Out Converter (LOC) or if your amp has high level inputs use those. With either of those options you splice the speaker wires (either the ones from the 6X9s or stock sub if you have one.... it doesn't matter its just convenience) and connect them to either the LOC or to your harness for the high level inputs. Some LOCs require a ground as well as the speaker wires. A few companies that make them are Install Edge, Bluewave, Scousche, Perpheral, PAC, Stinger, American International, Ect...
heres a good how too for more info How To: Install System on Stock Headunit!
18.) I want to replace my speakers what sizes are they and how do i do it?
All cobalts have the same speakers. 6.5" in the front door and 6X9 in the rear deck. For the cobalts with the pioneer package the speaker is just held on via 4 screws and can be replaced easily. For the non pioneer people the stock speaker is actually built into the braket that is bolted on the door. To my knowledge you cant order the ones that come in the pioneer package (that would be too easy) so you must fabricate something yourself. A piece of wood is normally what i would use. Cut to the size of the stock speaker/bracket thing with a speaker cutout.
19.) Whats the stock sub size?
The stock sub is a Dual 2 ohm 10"
20.) How do i remove the dash trim to get to the headunit?
Disassemble Dashboard - Radio and related panels
21.) I installed an aftermarket HU with my pioneer package cobalt and now my speakers wont play.... how do i fix this?
You must hook up the "remote" wire for the stock amp to the remote coming off the head unit. To do this you must cut the pink wire coming off the stock harness and connect it to the blue/wire remote wire on your aftermarket HU harness.
22.) What size is the stock battery and where is it located?
The stock battery is a group 34/78 and its located in the spare tire wheel well, in the bottom of the trunk
23.) Do only certain aftermarket head units require the antenna adapter or all of them?
Most aftermarket HUs will require the gm antenna adapter
24.) I have a system and my lights are dimming what do you recommend?
Normally the best thing you can do to prevent the lights from dimming is to swap the stock battery with a better one. I recommend the Carquest NGT Extreme Battery.
Its comparable to the optima yellow top with slightly better specs and more importantly a much better price. For you heavy hitters with the bigger systems you may want to bump it up to a Kinetik HC1800 battery. They are one of the best batteries on the market and work damn well but the price tag is going to be around double that of the optima yellow
I know there is a lot more to cover so you guys feel free to input your knowledge here so we can avoid these reposts.