[djjasond]

Background: I created these instructions and captured these pictures to help those who would like to remove the rear deck and gain access to the rear speakers. I have also included tips on removing the stock 6x9’s, making your own speaker adapter plates, replacing them with upgraded speakers, and eliminating rattles made by the 3rd brake light.

Disclaimer: This was a true Do It Yourself pictorial and as such may not be 100% technically accurate. The pictures are of a 2006 300C with Sound Group II. Other years and models may have slight differences. I expect follow up posts from the loyal members of this site with corrections as needed. The instructions also assume a basic understanding of car audio and the 300C’s audio options. Please be sure to read the Audio FAQ before posting any questions to this thread. (http://www.300cforums.com/forums/showthread.php?t=5298).

WARNING – Window Tint: If your rear window is tinted, use extreme caution. I would do this procedure before my window was tinted if at all possible. There are multiple opportunities to scratch the hell out of your window tint if you aren’t extremely careful. It can be done but do so at your own risk. I’ve tried to highlight them in the instructions below.

 

[djjasond]

1) Disconnect the negative battery terminal using a 10mm socket. Battery is in the trunk next to the spare tire. (picture 01). Once the battery is disconnected, do not close the trunk or you will be forced to crawl through your backseat into the trunk and pull the emergency release handle. This is about as fun as touching your toes after Thanksgiving dinner. I recommend taping the latch so that “helpful” friends and relatives are unable to close the trunk in your absence. The rear speakers are top mounted and therefore require the removal of the rear deck cover for replacement. (picture 02)

 

[djjasond]

2) Fold down the rear seats to gain access to the 10mm bolt securing the side cushions. (picture 03) The top of the cushion is connected to the frame with a v-shaped clip with the top of the “v” facing you. You need to apply pressure to the top of this clip to compress it and remove the cushion (imagine compressing this character “>” to a dash “-”). I slid a trim panel removal tool down behind the top of the cushion until it made contact with the top of the clip, applied pressure, and then gently tugged on the top of the cushion to remove it. (picture 04,05,06)

 

[djjasond]

3) Remove the lower side trim panel by removing the two Phillips head screws at the base of the panel and midway up the panel. Then gently tug on the top of the panel to release the clips holding it in place. (picture 07,08)

 

[djjasond]

4) Remove the upper trim panel by first prying off the airbag logo with a flat blade screwdriver. This exposes one Phillips head screw for removal. (picture 09) Gently tug on the panel to remove the five clips retaining the trim panel in place. Once you get the first one out, you can get your hand behind the panel to help ease the rest of the clips out. The seatbelt is fed through this panel. You can rotate the panel and get it out of the way without removing the seatbelt. (Note: Tint warning - You have to apply significant pressure to release the clips. There is huge potential to for this panel to pop off and scratch the tint.) (picture 10,11)

 

[djjasond]

5) Remove the plastic rivet securing the rear deck cover in place using a trim panel or pry bar tool. (picture 12) Pull the rear deck cover straight back and move out of the way. The seatbelt is fed through this panel. It is possible to easily move the panel out of the way and access the rear speakers. The rear speakers are top mounted and secured with four Phillips head screws each that can be removed with a screwdriver or 7mm socket. I recommend using a socket on the rear screws as the clearance is very tight. (Note: When removing the rear speakers out of their respective holes, the speaker magnet tends to stick to the rear deck. It then takes a good tug to release it sending it furiously towards your window tint. Keep a hand between the speaker and tint at all times!) (picture 13,14)

 

[djjasond]

6) Optional: Many of you will want to replace the factory speakers with aftermarket speakers of a different size. There are speaker adaptor plates available on the market which convert the 6x9” hole to a 6.5” or 5.25”. My experience is that they tend to be plastic, not that sturdy, and rattle happy. At a minimum, be sure to apply a layer of sound deadening to them. I prefer to make my own using ¼” masonite.

a) Use the original speaker as a template for the adaptor plate, tracing around the outside of the speaker and marking the mounting holes. (picture 15)
b) Draw a line from corner to corner to locate the center of the adaptor plate. (picture 16)
c) Using a compass, calculate the width of the cut out for the new speaker and then draw it on the template using the compass. (picture 17, 18)
d) Saw out the new cut out for the aftermarket speaker. Place the aftermarket speaker in the hole to ensure a proper fit and mark the mounting holes on the template.
e) Drill all the mounting holes for both the adaptor plate and the new speaker using a bit slightly smaller than the width of the mounting screws.
f) Cut out the adaptor plate and cover with a layer of sound deadening material.
g) Mount the new speaker to the adaptor plate and consider wiring the speaker as well. It’s easier to do it now then from underneath in the trunk.
h) Install the adaptor plate with the new speaker into the vehicle. (Note: You may want to consider bottom mounting your new speakers for easier removal or replacement in the future. I made the mistake of top mounting the adaptor plate but bottom mounting the speaker to the plate. I dropped it in the factory hole and “clank” – didn’t fit. My 6.5” speaker was too wide to fit (6.5” speaker into 6” of 6x9” hole… no comment). You will probably have to bottom mount the adaptor plate and bottom mount the new speaker to that plate if you want it accessible from the trunk for removal.)

 

[djjasond]

7)Optional 2: While you have the rear deck cover off, you may want to do some sound deadening over the entire rear deck. Search the forum for “sound deadening”, “dynamat”, and “fatmat” for threads on this. But in particular, the third brake light is a notorious rattle on this car. Thanks to Rogue for the heads up on this. To remove it:

a) Remove the electrical plug from the rear of the light.
b) The light housing is secured by two Phillips screws that can also be removed with a 7mm socket. After removing the screws, pry up on the legs gently to release the two locator pins which are next to each of the screw holes. The light is then easily removed. (picture 19)
c) The actual source of the rattle is inside the light. Remove the red cover by unsnapping it. Gently shake the light and it will be immediately noticeably that metal pieces under the LED’s are rattling against the board below it. Tiny dabs of silicon helped secure these metal pieces against the plastic housing and eliminated the rattle. (picture 20, 21)

 

[djjasond]

Look for similar posts on accessing the factory amp and removing door panels in the near future. Enjoy!

 

[HEMMISSEY]

only on 300cforums.com :fing02: again, excellent write up.. STICKY please..

 

[mikew2069]

Just dynamated my rear deck lid thanks to this thread. And I did it in about an hour. Whoohoo!!!

 

[djjasond]

Thanks Mike!

 

[mikew2069]

Thanks Mike!

No, THANK YOU DJ!

 

[Hemileejw]

1) Disconnect the negative battery terminal using a 10mm socket. Battery is in the trunk next to the spare tire. (picture 01). Once the battery is disconnected, do not close the trunk or you will be forced to crawl through your backseat into the trunk and pull the emergency release handle. This is about as fun as touching your toes after Thanksgiving dinner. I recommend taping the latch so that “helpful” friends and relatives are unable to close the trunk in your absence. The rear speakers are top mounted and therefore require the removal of the rear deck cover for replacement. (picture 02)

This is some good info but why do you have to disconnect the battery? There is not 12 volts going to tne speakers and you lose all of your computer and radio settings.

 

[mikew2069]

This is some good info but why do you have to disconnect the battery? There is not 12 volts going to tne speakers and you lose all of your computer and radio settings.

When he wrote this, I'm assuming that he was just trying to write it as 'text-book' as possible.....I did not disconnect the battery when I did it.....

 

[djjasond]

When he wrote this, I'm assuming that he was just trying to write it as 'text-book' as possible.....

Yeah man. Just trying to be responsible. This is actually 1 of 3 posts (amplifier access, door panel removal) that I wrote in a series and I was of the mindset that people would be adding aftermarket amps and speakers following these directions. If you plan to cut wires, it's a good idea to disconnect the battery.