I am working on a project that requires that I tap into the brake light wiring on my '14 991 C4S. As I prepared to start the project, I needed to determine specific wiring for the rear, third brake light, which is mounted within the engine compartment ventilation grill. I decided that to get to the light, I would have to remove the brake LED bar, which in turn requires that the entire ventilation grill assembly on the 991 be removed. I searched forever and didn't find squat as this is a newer model car and not many people have taken them apart. So, I decided to explore a bit, and take everything apart and document for future reference.

This DIY will be handy for anyone who would like to paint their ventilation grill, go aftermarket, or anyone who may need to pull the third brake light LED bar for service or troubleshooting down the road....

Let's get started!

Tools you'll need:

• T-25 bit
• Pair or two of basic needlenose pliers
• Masking or Painters tape
• Microfiber cloth or towel
• Small or micro standard screwdriver

That's it. You really don't need anything else other than patience.... I was able to get the grill off in a matter of a couple of minutes once I understood how the snap-in connectors worked, and how many of them there are. This is a very simple DIY effort in other words. Easier than changing a tire (and a lot less dirty) IMHO!

1. Open the engine compartment lid


2. Take note of the location of all the fasteners:

There are 4 T-25 screws and washers along the leading edge, and


9 retaining pin-tabs located around the perimiter


Also note that there is a rubber boot connecting the engine cover lid to the body at the right-rear. This is the wiring run from the interior out to the third brake light in the lid as well as the antennae 'bump'. I thought I might have to disconnect this, but in the end you will not unless you intend to remove the engine cover lid entirely....


3. Remove the 4 torx screws. Be careful not to drop them down into the fan assembly below!


You now find that the leading edge of the grill is loose, and you can pull it up quite a bit to see underneath.... but you don't want to pull too hard from this point or risk snaping something.


4. Go to the two retaining pins near the center of the lid -- to release these pins you will have to use a pair of pliers or something similar to squeeze the tabs together. While you are squeezing, wiggle the pin and push UP at the same time that from the other side you are pulling a bit with your free hand. With a bit of wiggling you should be able to push the retaining pin up through the hole to release.


Also be sure not to squeeze the retainer too hard, or twist it too much, as it will break. The pins are hard plastic, and easily broken. If you break one, my SA tells me they are easily replaced though!

5. After you have the two center pins released, lower the engine cover lid to nearly-closed position. This will give you some leverage to work the other pins out. Then start at one of the side front corners, and begin carefully pulling-up on the grill slats.

When the next pin releases, it "pops" out so be careful as you get further around the grill not to drop the grill and scratch it or the car body. You may find that the pins you can see along the back-edge of the lid need a little persuasion to release, so use your pliers again, squeeze and wiggle til they release!

In this pic you can see there is a retention pin just inside the opening.


I found that as I pulled-up I ended on the left corner, closest to the point where the brake light wiring goes up to the grill. I then placed a microfiber towel over the rear window and exposed body work and flipped the grill upside down onto the towel.

Pic of the wiring to the brake light as I pulled-up on the grill:



Lift the entire grill up...


And put a towel down to protect the grill from scratches.

Here is a pic of the grill removed and placed on the rear window


Several immediate observations:

The wiring connecting to the third brake light looks flimsy. There is a RED/BLK wire (I believe this is power) and a BRWN/WHT wire (this is probably ground).

With the grill removed, I noticed a LOT of dirt built-up on the engine lid... Now would be an excellent time to clean it off!

The filth!


After a good cleaning, I also noticed the manufacturing stamp that includes part number...


6. Release the connector to the third brake light. Using a small micro-screwdriver, release the tab and push the connector off. I would recommend NOT to pull it off by the wires, as it seems like you could easily pull them out....




After you have the wiring disconnected, take the grill over to a safe spot -- I used a surface covered by a carpet and microfiber towel.

Here's what you'll be looking at once you've removed the grill cover and cleaned-up the engine lid:


You're done!

Hope you find this helpful someday in your own projects or curiosity! See my DIY on Third Brake Light Removal if you'd like to get the LED bar out....

 

Another ★★★★★ post!

 

Ditto!!

 

Once more - you da man! Great post. Thanks again (and again, and again)

 

Just used this to replace the grill... thanks and kudos to jon for another helpful diy...

A couple of suggestions for posterity..

1) you can actually remove the brake light before removing the grill... you can pry it out carefully with a plastic body tool... and then disconnect...that way you dont have to fool with the wires after you get the grill loose.. either way is fine though..

2) the two plastic pins at the upper left are obscured (at least on a c2s) and you have to reach in the access hole and it is impossible to get pliers on them to release.. however i found if you use a plastic body/interior tool with just the right size split fork, and work it you can use this to release fairly easily.. actually i found this works on all the pins easier than pliers, but the fork end needs just the proper round cutout...

 

What do these tools look like and where can you purchase one?

 

http://www.suncoastparts.com/product...iorAccessories

 

Yep those will do... The one that is the second from the far right in the picture is what I used...

Also you can get the same kit from harbor freight for about $5 if you were in a hurry..

 

Wow 14 bucks that must be the cheapest item on the menu.

 

I just did this on my car. Thanks very much for posting details.

One improvement I have is to use a 6mm 1/4" (6 point) socket to press over the retaining pin instead of using a pliers. The socket compresses all 4 legs of the pin and they pop out in a second with a loud snap. You can get to all the pins except the two in the rear (front of car). Those I just used a pry tool and they popped out.

 

Man..seen this before and saved it and finally got the time and additional funds allocated and went ahead and purchased the OEM GTS rear grille to replace my OEM one and thanks to this thread the replacement went great. Very easy with this DITY and took me only about 25 mins max from start to finish including brake light swap and re-installation of new GTS grille. Thanks again man!

Yes hard to get those however I found the pry tool useful and also once you get all other fasteners loose these were easily able to pop out with a little bit of pressure.
This worked well on the easy to reach outside fastener points. Great idea!

 

Nice Job! I did the same swap, I absolutely love the transition from stock. Yes, expensive swap but really worth it at the end. If anyone needs a GT Silver Replacement louver for their 991 I have a brand new ready to go. Just PM me.

 

Thank you so much for the great instructions for the vent removal.

Is this same vent also compatible with a 991.1 GTS "convertible"?
It wasn't obvious from the Suncoast Parts website here: https://www.suncoastparts.com/produc...TSGRILLES.html
if this is identical to the one used on the convertible.

I sincerely appreciate the feedback. I thought I'd ask the experts at the forum before I order for $1,700

Lorenz