I was driving the Miata across town, after it had been sitting parked for many months, and had forgotten how great the shifting felt after I had rebuilt the shift assembly in that car. The NA Miata has the advantage of the shift assembly being built directly into the transmission, which rides in the hump between the driver and passenger seat. (As I am resurrecting this blog to talk about car projects, I’ll get back to what is going on with the poor Miata in a future post. I am going to be working my way backwards on projects, and most of the Miata story happened in 2024.)
Around 10 months ago I picked up a used 2007 Cayman S. During that entire time, the feel of the shifter I would describe as “mushy”. There is a lot of wiggle whether in-gear or not. I got used to it but never really liked it. Driving the Miata made me think, why can’t I just fix this? So I did some research and decided, ok, clearly the answer is a Numeric sport shifter assembly and shifter cables. Having not dealt with them before, I did not fully understand how the shifting by cables worked and that it may have been possible to just adjust the play in the cables without upgrading the assembly. (Quick tip, if you are in that situation, don’t want to spring for expensive upgrades, and are up for pulling apart the dash, you should be able to try adjusting the cables to have less wiggle).
Meanwhile, if I was going to have to pull the whole dash and center console apart anyway, I might as well finally figure out how to install the rear view camera I’d bought months ago and put in a head unit I actually wanted, something with wireless CarPlay. Would it not be better to do this all at once? Hah hah hah. As it turns out the stereo-related work took about two days and the shift assembly work about two hours. No regrets.
As there is not particularly good documentation on how to route the wiring for the rear view camera specifically in the 987.1 Cayman, I am going to focus on that piece of it first. Then I will follow up with routing the CarPlay+GPS antenna, and a few notes about the interface to the BOSE fiber optic sound system when you have that option. In my next post, I will finish up with some notes on the Numeric sport shifter install (I did not get to the shift cables, for reasons I will discuss in that post).
Rear Camera Install (987 Cayman)
There are a number of videos online that show this for the Boxster but none that I found detailing the Cayman. There are videos of people removing their entire bumpers, drilling holes, doing all kinds of crazy stuff. That feels like too much work for the benefit to me. I opted for a relatively cheap license plate light replacement kit off AliExpress. There are a number of different camera options from different vendors. I bought one kit that had a camera built in, and another that was just the light. They were from different vendors but the exact same light/mount part. This wound up being a stroke of good luck for a different reason, more later.
So the thing that tripped me up for the longest time was not realizing how easy it is to remove the tail lights, and that doing so exposes a big hole straight down to the license plate lights. You remove 3 8mm nuts and the tail light comes right out. In fact this is what you have to do to change the lights in that housing, so it makes sense that it is fairly easy. Access to that is behind a quick-release plastic panel and a carpet panel you need to remove to do the full job.
I pulled the long RCA cable through to the license plate, then connected it to the camera’s RCA cable, taped those together, and pulled them back up to the tail light fixture. There is enough room behind the tail light to hide all kinds of things but definitely enough for the RCA plugs. Next you need to connect the camera power to ground and to the reverse tail light. You will read in forum posts that the reverse light wire is blue/black, and I also found that to be true. However, please check with a multimeter! Put the car in reverse and see if it registers 12V. A vampire tap on that wire is the easiest way to power the camera, and you can use the nearby post to ground the camera power.
Tail light wiring harness. Reverse power is blue/black, position 3.
This would be a good time to test the camera. Assuming you have the head unit exposed, toss the RCA cable up front and plug it in. Turning on the ignition should start the head unit. Putting the car in reverse should let you see the reverse camera through the head unit. Success! Or if not, troubleshoot your wiring.
A note here about the license plate light mounts I used. There are two lights used to illuminate the license plate. Those lights have a simple wiring harness and are loose but tied together. The stock light harness attachment point is basically pointing up and back from the center of the light fixture. However, the new light fixtures had their harness attach at the far end of the fixture. The internal wiring was not long enough to connect the aftermarket light with a stock light. Fortunately, I had purchased the extra aftermarket light fixture (with no camera) that was the exact same configuration as the one with a camera, so I was able to use that in place of the other stock light, and didn’t have to modify the length of the wiring. Also, now the lighting is consistent as both lights are the same. And, both are way too bright! The LED lighting looks ridiculous (to me, I think 90s-era car lighting should look incandescent, not daylight white). I have yet to fix the color temp and brightness of those LED lights. In the future I will apply a film gel or something to get the right brightness.
Now to get the RCA cable to the head unit. Watching the 986 Boxster videos was not particularly helpful due to the difference in how the trim works with the drop-top. I read a forum post that mentioned popping up the faux-metal plastic trim, and that helped me create a plan. Use your trim-removal tools and pop that up a bit on the driver side (I had removed this trim before to replace the shocks and springs, so was comfortable doing so again). There are two screws under the little oil and coolant door. Those do not need to be removed but don’t go crazy and break the trim. Take the foam noise cover off the motor access panel, and route the cable up and around the outside of that area. Gently pull the carpet that runs up to that piece of trim out of the way. I used a lot of tesa 51036 tape for this project, and made sure to tape as I went, and tape the cable up and out of the way of the motor access panels.
I have seen forum posts by people who send the cable across the door sill; since I had the center console removed, I thought it more elegant to send the cable through the center console. Pull the carpet behind the driver’s seat back, and tape the cable down and around the motor access panel. Send it out the center, where the console plastic will hide its exit from the carpet. Follow the shift cables but make sure not to route the cable somewhere it will get impinged by the shift cable movement or the parking brake mechanism. You can fairly easily push the RCA cable through the hollow under the shift assembly, and slide it forward until it exits behind that dash structure. Just push on the slack cable and give the plug a nudge if it gets hung up anywhere, it isn’t too difficult. There is wiring in that hollow to use as a guide. Up around the back of the dash and you are done! The whole process is a minor pain in the ass, but do it right once and never think about it again. Hopefully. 🤞
Head Unit with Carplay/GPS install when you got the BOSE
This will be shorter. The main trick here is to have the right equipment to plug into the BOSE system and know that there is a “right” place for the GPS antenna, and a “right” way to get it in the cabin. Starting with the BOSE system: I bought the head unit from Crutchfield as it seemed like they would send me the correct adapting hardware. I trusted Crutchfield to send me the right adapter, and they came through. The Connects2 adapter kit they sent was perfect. I recommend this kit. Before installation, I recommend studying the CTSPO005.2 product page as well as the online manual – it is more detailed than the printed instructions that comes in the package.
The key thing to understand is that the BOSE configuration with the Porsche 987.1 has two wiring harnesses and a fiber optic connector with two fiber channels. The Connects2 kit has an adapter box for the fiber connector, adapters for the two wiring harnesses, and another little break-out adapter that provides steering wheel controls and a few other useful outputs. You get a lot out of these boxes! Reverse, parking brake, speed pulse, as well as the usual ignition and illumination signals. It’s pretty great. Where Crutchfield failed me was in providing a female ISO-16 adapter to plug directly into the male ISO-16 adapter provided by the Connects2 device. Since I didn’t want to wait around to get one shipped from… where ever… I just snipped off the Connects2 ISO adapter and butt-connected the wires directly to the new head unit wiring harness (that plugs into the head unit). This is less elegant than I would prefer, but about what I expected to have to do. A little more knowledge and I could have made this install a bit cleaner.
What you do NOT get in this setup is anything other than left/right audio inputs. The aftermarket box I replaced with the Connects2 had 4 RCA inputs (front/rear left/right), but I tested and there was no front/rear differentiation — the rear inputs were for show. There may be some super-expensive box out there that can feed the fiber optic amp system more than two channels of audio, but I haven’t seen it yet. I wonder if the stock system did more than two channels of input to begin with. With the Connects2, you cannot do front/rear fade. Why you would want to do that, I have no idea. But there it is.
The installers of the previous aftermarket head unit in the car had somewhat mangled the stock wiring. This was required because they had a less-useful adapter box than what Connects2 provides. It took me a lot of time to puzzle out what they had done and to reverse it. Fortunately no serious harm was done and I was able to restore the factory wiring harness configuration.
Carplay/GPS antenna install time. This goes deeply under the windshield wiper cowl, passenger side, to the right of the cabin air filter. Why does everyone on the internet say this is where it goes? Because that is where the factory navigation GPS would go! It turns out to be a great open space for the GPS to get a signal, as long as you don’t cover it with the metal frunk lid (thus, the instruction to tuck it deep under the plastic cowl). These instructions from cai-store.com are terrific, I recommend following these. Slightly moving the battery, removing, cutting and reinstalling the grommet, it’s all a perfectly cromulent way to do this job.
My one note is that the grommet is surprisingly high up when you are under the driver’s-side dash. This is where I did the most damage to my back, trying to manipulate that grommet. Definitely not pleasant but ultimately I got it out and got it back in without too much trouble, once I accepted the awkwardness of the task at hand.
Final installation note: if you are replacing an aftermarket head unit, you will probably be dealing with this trim kit or similar. Take a good look at that diagram of the side pieces. The big tabs connect to the faceplate trim, which is relatively easy to get off. However, pulling the actual head unit out is extremely difficult! There are four small tabs behind those mega-tabs that are impossible to dislodge. I had to get two trim removal tools, jam one in each side, and methodically wiggle each tab out of location to get the damn thing pulled out. Conversely, be careful slotting in the new head unit with this kit — the bottom can easily get jammed in way too far, and is really hard to get into the correct position! It is a very weird kit that has a lot of gotchas. I’m not even going to go into the screws, which were a whole other issue.
References
I am linking to a few threads I found useful throughout this process. Huge thanks to all of the car-hacking authors out there blazing the DIY trail for the rest of us. I incorporate much of the information into my description above, but everyone finds their own preferred approach.
Rear camera install
- https://www.boxa.net/topic/95612-987-rear-camera-installation/
- https://www.planet-9.com/threads/backup-camera-install-15-mins.11162/
- https://www.planet-9.com/threads/boxster-987-2-front-and-rear-camera-install-completed.239781/
GPS antenna install