Latest Head Unit Replacement (Avic 120BT)

We did a head unit replacement in a Cayman S w/ Bose over the weekend with great success using the MOST HUR 997. So I will briefly go over the install in a moment. Before I do so, I want to take a moment to address some of the questions I routinely answer regarding the different sound packages for Gen 1 and Gen 2, this pertains to both 987 ( Boxster , S, Cayman , S) and 997 (all models). Also I want to briefly address some of the variations you may come across regarding Pioneer and Kenwood during wiring up the units. Gen 1 9X7 Non Bose (Standard or Sound Package Plus) If your car is standard equipped or you have the Sound Package Plus, installing an aftermarket radio is simply a head unit swap, no amp bypass or aftermarket amps required unless you want to. The harness adapter supplied with our kit includes the 8 pin speaker connection and also the amp turn on signal for the ASK amp in the Sound Package Plus. This install is relatively easy if you can follow instructions. Gen 2 9X7 Non Bose (Standard or Sound Package Plus) If your car is standard equipped or you have the Sound Package Plus, installing an aftermarket radio is simply a head unit swap, no amp bypass or aftermarket amps required unless you want to. The gen 2 adapter supplied with our kit includes the 8 pin speaker connection. For vehicles w/ the Sound Package Plus, the factory blue harness (part of the factory quad lock connector) has a white/red wire. The white/red wire is your amp turn on signal, it needs to be wire tapped in order to activate the ASK amp. This install is relatively easy if you can follow instructions. Gen 1 and Gen 2 9X7 w/ Bose If your car is equipped with the Bose Surround Sound System, you technically have 2 options when replacing the factory head unit. Option 1 - Bypass the factory Bose amp A harness adapter is available to connect to the speaker wire harness of the vehicle should you decide to go this route. An aftermarket amp is highly recommended. This install really should be done by a professional or an experienced installer. Option 2 - Integration w/ the factory Bose amp NAVTV MOST HUR is required to interface with the fiber optic signal input used by the Bose amp . This install is relatively easy if you can follow instructions. Regarding the variations between head units, as it pertains to the harness adapters. Pioneer seem to have done away with a dedicated Power Antenna wire in their newer model head units. Your vehicle however still has a power antenna wire as part of the factory harness, so in order to provide the signal for the power antenna, the "System Remote Turn On" wire which is used to switch the factory amp (or an aftermarket amp) must also be connected to the power antenna. This will allow A.M. reception in most cases unless you live in a very rural area. In reference to the Kenwood units, many of them today do not have a VSS (Vehicle Speed Signal) wire, so it is simply not addressed during the installation. If you have any particular questions you would like addressed, feel free to contact [email removed] . Below is conceptually how you would do an amp bypass on a vehicle w/ Bose set up. It's a bit more complicated than that but just a visual to help make sense of everything. A diagram w/ color codes is also provided below to show the different color wires associated with the Bose harness adapter provided to avoid splicing the speaker wires during the amp bypass.

On to the install using the MOST HUR. I will post the parts in the kit used and then discuss what was needed to be done to the car and the head unit. Then I will discuss how it works, the sound quality and some of the things you should be aware of when using the module. From right to left, the first picture is the premium kit we offer for those that want to keep the entire Bose system intact, it includes many parts of our standard kit along with the MOST HUR components. The second picture is the modified harnesses we include with the premium kit. The black harness is stripped of any unnecessary wires to minimize clutter. Leaving only 3 wires that will connect to the vehicle's 8 pin connector for ground, battery and power antenna. The salmon colored harness is something we took from our 9X6 kit, stripped it of all the RCA wires, leaving it with 2 wires to address CAN Hi and CAN Low. The last picture is the MOST HUR itself. While it may seem somewhat complicated, it is a very simple device to use. I will explain how it works and how the harness adapters we provide (picture 2) works together for a very seamless integration with little to no splicing whatsoever.

First, we will do some preliminary wiring. This part is very simple, especially if you just follow the instructions provided below. The bulk of the wiring connections made are actually from the head unit to the MOST HUR wires. 1. Head unit RCA cables to MOST HUR connection cable: Connect Front & Rear RCA Outputs to corresponding RCA's of the connection cable of the MOST HUR (Red RCA is the right channel, and White RCA is the left channel) 2. Head unit wires to MOST HUR connection cable: Connect VSS to pin 16(green/white), ILL to pin 8 (Orange), Parking Brake to pin 15 (Green), System Remote to pin 5 (yellow/black), Reverse Signal to pin 7 (purple/white), IR Control to pin 14 (white) (IR Control is only supported if you have Kenwood or Alpine and also if your vehicle has steering wheel controls), Accessory Signal to pin 17 (red)...the pin locations referenced above correspond to the wires of the connection cable. (Only exception is if your vehicle is a manual, you will need to tap the reverse signal from the rear tail lamp since CAN bus does not provide this signal for standard transmission vehicles). If you plan to do the parking brake bypass modification, then you simply will not address the Parking brake wire of the module. Same thing goes for any wires not relevant to your head unit, such as the IR signal, you will simply not address them if they're not needed. Next , we make the connections w/ the harness adapters supplied in the EMS kit. 1. We take the 12v constant ( battery ) wire from the head unit, along with the yellow wire (pin 1) from the MOST HUR connection cable and connect BOTH of those wires to the 16 pin black harness adapter's yellow wire. 2. We take the ground wire from the head unit, along with the ground wire (pin 10) from the MOST HUR connection cable and connect BOTH of those wires to the 16 pin black harness adapter's black wire. 3. We then take the power antenna (blue) wire from the 16 pin black harness adapter and connect to the System Remote wire of the Pioneer 120BT. (This is specific to recent Pioneer head units, your head unit depending on the manufacturer may have a dedicated Power Antenna wire) 4. The salmon color harness adapter then connects to the CAN Hi and CAN Low wires of the MOST HUR connection cable. a. Purple wire (CAN Hi) of the salmon color harness adapter connects to brown wire (pin 18) on the MOST HUR connection cable. b. Green wire (CAN Low) of the salmon color harness adapter connects to brown/red wire (pin 9) on the MOST HUR connection cable. Note: Only a few wires (5 wires plus the fiber optic connection) from the connection cable and the head unit are connected to the vehicle using the supplied harness adapters - allowing you to avoid splicing any wires in most cases. The pictures below show the factory harnesses we will plug into the harness adapters once we are ready to install the head unit. (We won't get into the details of radio removals, and some of the other procedures involved as this has already been covered by our previous DIY, which we go into great depths about things such as disconnecting the ground cable of your battery before you begin work on the radio installation). From left to right, the first picture is the 8 pin factory harness which will supply battery , ground and connects to power antenna. The second picture, we have the 8 pin factory harness plugged into our harness adapter. The third picture is the factory harness which includes the 6 pin C1 plug which provides access to CAN Hi and CAN Low. The fourth picture shows the CAN Hi and CAN Low harness plugged into our harness adapter. Once the factory harnesses are connected to our harness adapters, we will also take the fiber optic extension cable supplied by NAVTV and connect it with the fiber optic cable of the vehicle. We then route the MOST HUR connection cable and the fiber optic extension cable down underneath the dash (behind the carpet panel). Here, we will connect the actual MOST HUR module. I prefer to place the module behind the dash or somewhere accessible as oppose to trying to fit everything behind the head unit which can be quite crammed. We then connect all the necessary plugs into the head unit, reconnect the ground cable of the battery , test to make sure everything is properly working, and finally put everything back together.

So here are the benefits I see with using the MOST HUR. 1. Installation is considerably more simple and less labor intensive. In most cases, many of the signal wires (Illumination, VSS, Parking Brake, Accessory Signal, Reverse Signal, System Remote) of the head unit receive signals through the module via the CAN Hi and CAN Low connection to the vehicle, eliminating running a lot of wires/RCAs in the amp bypass method. 2. No alternator whines or noise feeds. This is probably one of the greatest advantages over using an aftermarket amp. With an aftermarket amp set up, if you have a humming or whine...the agonizing part is trying to isolate the source of that noise or interference. Reading other members who've gone this route, I know it can be sometimes frustrating to troubleshoot this issue. Using the MOST HUR, the digital sound sent through fiber optic cables do not pick up noise interference when transmitting to the Bose amp . 3. In most cases, very little to no wires are spliced in the process. So returning to stock simply means pulling out the aftermarket radio, unplug the harnesses and reconnect the original head unit. (All of our kits are in fact designed to be minimally invasive, and includes parts designed to integrate as much as possible to your factory set up.) 4. This is going to be depending on your stereo budget, but for the vast majority of people the MOST HUR will provide an improved and more than satisfactory experience w/ your aftermarket head unit. The reason being, simply is that radio manufacturers such as Pioneer , Kenwood , etc. do provide a premium radio in comparison to the stock unit. With aftermarket radios, your going to get improved sound quality and more powerful output compared to stock. Furthermore, the various equalizer settings on these aftermarket head units really help fine tune what you hear to your preference. 5. All of the speakers remains in use in a very simple set up versus trying to figure out different methods to address the various speakers and the self powered sub when bypassing the amp. As you can probably tell, I really like installing using this method now that I have had a chance to do one locally. It was technically a breeze to install, and I didn't have to do much wiring to get everything to simply work and worked great to be quite honest. Below are some pics of the finished product. Not really much different from any of our other installation pics but it's my most recent pics, enjoy. If anyone is interested in going this route or have questions, feel free to contact us [email removed] done this first hand, I can walk you through it no problem. Kind Regards, Loi

Great series of articles, really clears up some things. Can you address the performance/sound from the Bose system with the Most-HUR. I talked to a local installer and have read it here on the forum, that the sound quality and performance is better with after market amps, speakers and wires. Also can this upgrade be accomplished with most aftermarket head unit? Thanks, Ron

Hi Ron, This upgrade can be done with the majority of aftermarket head units, and in most instances you don't need to fiddle with updating the software via the USB port on the module. The one downside though with using the module is you lose the ability to use fader control from your aftermarket head unit. It's a technical challenge from what I understand to make such adjustments from an analog head unit to a digital signal going to the Bose amp . Bypass the Factory Bose Amp . Without a doubt, changing the amp (and possibly the speakers) out in addition to the head unit will dramatically improve the sound quality to a very high degree and may be a more ideal solution depending on your requirements. A quality aftermarket amp will do an awesome job filtering the frequencies and give you very clean, powerful sound to your speakers. You can go pretty extreme, the skies the limit as far as what you can do with aftermarket components...pretty much whatever your budget can afford. The case for the MOST HUR. While not intended for everybody, the module is more ideal for the vast majority of folks who want to achieve a few things such as improvement in sound quality, add/replace navigation, XM/Sat, Ipod and Bluetooth...the module will be more than enough to meet those needs in a very uncomplicated manner. It's also ideal for people who want to do the install on their own that have limited installation experience...this option makes it very simple and you don't have to worry about things such as alternator whine feeding through your speaker system. As I have done the install both ways, this method is definitely a walk in the park compared to running wires & cables and addressing all the channels of the Bose speaker system. Hope this helps! Cheers, Loi

I agree and I fall into this camp. I had a demo of a Clarion NX501 and I liked all the things they had done. One of which is integrated the mic into the head unit so you don't have to wire the mic remotely. The demo unit in the installers car worked well. I may do this myself and I don't want to be pulling panels all over the place to wire in a mic or speakers. As long as the quality is better than what I have I like this route. Thanks, Ron

Hi Ron, That explanation works, thanks! Your balance settings will still work as usual F.G., you just won't have any adjustments from front to rear. Cheers, Loi

Hi Loi - Thanks for your information yeterday via email. I have an appointment to resolve the problem of Fade. In my particular situation I am going to a) use the powered output of the radio to drive the rear speakers or b) install a small remote amp to drive the rears. The installer who did the initial install also offered up the full amp replacement.... Given that a Boxster is open top....90% of time...I think a) is preferred and b) is backup. If these do not work, then I will bite the bullet and do a full amp replacement. Thanks again for your write up....it was both timely and very informative. Dan :cheers:

Hi Dan, You're welcome! Btw, I have a theory you might possibly test, give me a call when you have a moment. Cheers, Loi

Superb, thanks so much for taking the time to write this up. I plan on doing my own upgrade/install next year so I'm archiving this essential information. Are there any aftermarket amps you could recommend that can be installed in place of the factory amp? I'd rather not take up space in the front trunk.

Hi Allen, We wouldn't be able to offer you much help in this area, as we only do installs on a very limited basis. Our installs are mainly done for DIY and product support purposes, so we wouldn't be the best source for such information. I recommend contacting a local car audio shop to help you make an informed decision regarding amp selections. A year from now there may be even better options available, so you'll definitely want qualified people offering you advice. Plus, when you're replacing both the head unit and the amp, it can be a bit finicky and it sometimes boils down to the quality of the components. As far as what we come across talking w/ customers, the JL XD600/6 seems to be one of the more popular amps for this type of upgrade. It's a relatively affordable amp at $499 (you still need an amp kit and RCA's). And it's footprint is small enough that it can fit underneath the plastic cover of the front trunk or even replace the Bose amp (where the tire inflation kit is located). Cheers, Loi

Do these after market head units require gps antenna's like the factory unit? What is a good head unit with GPS , iphone , Bluetooth that works well with this kit. What is the cost of the premium kit? Is anything else apart from a head unit required with this kit or is this it? Thks. G

1. Yes, a NAV unit will require a GPS antenna. It should come with your unit. If you already have PCM, you might be able to use the factory antenna. Many of us have mounted them in the front trunk in an area near the wiper motors, under the fake carbon fiber cowling. Therefore it is hidden from sight. Doesn't seem to suffer from reception problems. 2. Any Double DIN (2Din) unit should work. The only restriction would be the depth of the chassis. I wouldn't go more that 6.5 or 7" deep. Although there is lots of room back there, you also need room for various wire harnesses and adapters - plus enough space for cooling ventilation. Most of these units have small fans to cool them. 3. The Euromotorspeed kit is only the bezel, mounting rails, and various adapters. See the pics on post#2 in this thread. Looks like the Bose version can be bought with an additional MOS adapter. If you want a backup-camera, XM/Sirius/HD/Traffic/BT/iPod adapter(s) for your chosen HU, those (or some of them) will likely be extra. They have nothing to do with this kit, per se. However, I'm sure Loi could give tips on the best way to connect or run the wiring.

Hi G, Only if the double din unit have navigation does it require the GPS antenna (it's included when you purchase the head unit new). A suitable place for the antenna is underneath the windshield plastic cowl. It is accessible from the front trunk behind the battery area. You will get good reception putting it there and it will be out of sight. As far as a good head unit, you might want to take a poll of what other forum members prefer. Aesthetically, I like the Pioneer 120BT (or the newer 130BT), full screen size fits the decor of the interior nicely and w/ minimal clutter. If you prefer the Garmin mapping system then you might lean towards a Kenwood unit instead. There are quite a few options when choosing a head unit, all depending on your budget. By the way if anyone is looking for a good deal on a 120BT, one of my customers pointed me to crispdeals.com. They are selling the unit for $949 shipped, I shopped around online and that seems to be a pretty good price. Btw, we have no association or affiliation w/ crispdeals.com...they are a Pioneer authorized DJ reseller and a few of my other customers have bought from them as well, but do your own research before you decide to buy. The premium kit which includes the MOST HUR 997 is $800 (plus shipping if you are outside of the US). Kind regards, Loi

Ron...you beat me to the punch. I'm a slow typer Cheers, Loi

I have a manual transmission so whats with the reverse wiring? Is that for a back up camera or something? Also, whats the handbrake override thats also referred to in the article? Thks. G

On many (or most) head units that support a backup camera display, there is a wire that typically is to be tapped into the b/u light circuit. When energized, it switches the HU display to the camera input. Note: Pioneer NAV units also use this for dead reckoning, when you can't get a satellite position fix (like in a parking garage or tunnel). The unit knows your speed from the VSS sensor (if connected) and the b/u circuit says whether your motion is forward or back. Note: both VSS and BU connections are optional - but should be done as part of a professional installation. All aftermarket and AFAIK factory NAV units have a parking brake lockout that disables many of the NAV and other functions unless the parking brake is set. The HU's parking brake circuit must either be correctly connected to your parking brake switch, or by-passed using a published hack that defeats this lockout. If you've ever used a NAV then you know how irritating it is when neither you nor a passenger can enter a new destination unless you pullover and park.

Ron, very awesome!

Thanks, Loi. But you're the master. I should also have added that whichever HU you consider buying, do some research (via your fav search engine) as to whether a bypass is possible, and how it is done. For the Pioneer Z1x0-BTs it is simply moving one wire in the harness and grounding it along with the normal PB wire. There are even several instruction videos on YouTube. The Z110 & Z120 are the same units (just different firmware), so the instructions are the same. If you get a Z130-bt, the harness connector is different, but the procedure is basically the same. For excellent user support on any Pioneer NAV units, check AVIC411.com.

I had meant to post this a week ago but got caught up in my final rounds of rotations here before i'm done! so excited. and even better, my radio works. I wanted to follow up with my personal experiences with Euromotorspeed and the MOST HUR. I have a Porsche Cayman with Bose and after I installed my aftermarket radio I had an annoying alternator that drove me crazy. The sound seemed to get worse as I stepped on the gas. The worst part was, even if I had the volume turned down to zero the whine wouldn't go away. It was so bad that I often chose to unplug my amp altogether and listen to music through my headphones. I took it to two Best Buys and two different car install bays. We tested the amp & radio, switched out the grounds, upgraded the RCA cables and even tried to suppress the noise with a ground loop isolator with no success. After countless google searches, I came across several postings on the forum where Loi came highly recommended for his support with radio installations. So I gave him a call and we discussed some of the issues I had w/ my existing set up. Loi asked if I would consider using the MOST HUR to eliminate the noise feed. After a few email exchanges, I decided to make the 3 hour trip to Tampa (i'm in ft laud) and see if he could fix my problem. It honestly took him just under an hour to install the MOST HUR. No more whine, not even a hum. I’m no audiophile but I do consider myself a music junkie. Music with the module installed sounds awesome. The sound is crisp, tones are right, and treble and bass is pretty well balance (after I made a few minor tweaks to my head unit's equalizer settings). I can truly enjoy driving again!!! Apart from installing the module, he also brought out his install kit to show me how it worked and how close the paint match was, SOLD. He swapped out the original one I had purchased from the UK, I can't believe how stock it looks in comparison. Loi's attention to detail is top notch, now I understand why many of the posts I've came across have nothing but good things to say about him and Euro Motorspeed. My old bezel that I got from the UK (trying to return) was sold to "match" the interior but when I got it it was just a flat grey paint. The sides had to be beveled to get them to work and even then it popped out and refused to remain flush. I had to hot glue it to get it to stay in. Euro Motorspeed's kit just slid on, snapped, and it was over. Looked exactly like the factory paint and was perfect flush. I was impressed. I don’t know how long the kit has been around but to me it’s a no brainer and worth every penny. I always thought that whenever you have Bose , you absolutely had to get an aftermarket amp. Euro Motorspeed’s solution lets you use the existing factory amp and seems easy to install (though I pretty much just watched). With the Ben Hur, you wont need high end RCA's, you wont have to purchase an amp and then find a place for it (i spent an hour building a damn box) and you wont sit on your back for 3 hours running wires through cramped places. IF you add in all these expenses, its actually cheaper to use the MOST HUR instead of the new amp method. I don’t know how widespread the alternator whine problem is with Caymans or Porsches in general but I’d definitely recommend anyone installing an aftermarket radio to consider going this route w/ the Euro Motorspeed kit. Save your cash and time. Thank you Euro Motorspeed! (especially Loi)

Does the MOST HUR allow the song info to be passed to the speedometer display? I'm almost certain the answer is No since it would require the headunit to send the appropriate information, but who knows, just thought I'd ask since it taps into the CAN bus .

Ron, we will have to promote you to Jedi status...hope all is well w/ you. Have you started going to any of the PCA meet ups for the Suncoast region? Spyd3rr. No information sent to the speedo, that takes a level of integration only a factory radio or PCM can provide you with. In regards to CAN bus and the module, it does nothing more than feed your head unit with the necessary signals...illumination, reverse gear, switch power (ACC signal), etc. Apart from that, it is an integral part in making sure the audio signal gets sent to the fiber optic output...get the wires reversed and no sound comes out. Thanks DoctorPorsche for posting your experience, appreciate the feedback! Glad we were able to help you with your install. Cheers, Loi

Ordered my Premium Kit from Loi today. I'll post some pics and a review when I get it in the car. Can't wait. Now to figure out what HU I want.

Probably going to wait a bit and see what comes of this................. Pioneer developing iPhone-like multitouch head-unit — Autoblog

Does the AVIC come with HD Radio? It looks like it's compatible, but isit standard? Anone heard HD radio yet?

I just finished the install of the EuroMotorSpeed bezel kit and a pioneer 8000BT.... 5 minute call to Loi is all I needed after I had read the instructions and looked at everything carefully.. Couple minor notes: 1) Euro instructions speak about the switched accessory power in the 911 (997) section (referring to the double fused part of the kit going to C6 in the fusebox)... I bypassed this section of the instructions as I have a CS. Anyway, Loi confirmed C6. 2) Illumination wire... instructions say to tap into the driver side brake light assembly... (WAY too far for what I was doing) so Loi confirmed that a signal to tell the system that the parking lights are on is what is required... so he suggested the cigarette lighter has a light ring (turned on w/ the lights)... Bingo... verified before cutting voila... (you want to join to the small orangish wire... the other two are thicker and for the cig lighter itself) 3) Euro harness has two blue wires (antenna and amp - w/ white stripe)... anyway, they both need to join to the pioneeer blue/white (as there is only one) Still getting used to the head unit... but sound is already MUCH better... and the iPod sounds great (no FM modulator) and is FAST to operate... Cost: Euro - $250 HU - $260?? ( amazon ) - don't need NAV or DVD. oh... one last thing I remembered... It was not obvious (to me) how the Euro faceplate attaches to the front of the HU... it doesn't... the 4 spring clip things in the kit get screwed into the side of the new HU... w/ the arms through slots in the side brackets... and the face plate clips onto the end of those springy arms...

Hey. How long did it take you to do? How knowledgeable would you say you were of this type of thing in general? I would love to do this, I'm just concerned that I'll bite off more than I can chew. An experienced installer in NC would be the best case scenario but an understanding of exactly how complex this really is would be a close second. Thks. G

Hi Loi, A quick question on the MOST HUR's lack of front/rear fader. I understand that it's stereo only. Does this mean that one loses the rear channels entirely or just the fade function? Cheers,

Greywolf, you essentially just lose the fader functionality. Gmorat, the install takes approximately 1-2 hours* w/ the MOST HUR if you are just doing a head unit replacement only (not taking into account rear camera or reverse wire for manual trans). *That does not include time required to solder the various wires to the MOST HUR connection cable. But we have a couple of great options to simplify soldering for anyone interested. For a limited time, send your head unit's connection cable to us and we will solder seal most of the wires up to the MOST HUR for you, it's a good choice if you're not into reading instructions. Or if you prefer to do it on your own, the kits will now include the premium solder seal connectors. You can use a heat gun or a torch soldering tool.

What technique did you use to get at the cigarette lighter wire? Did you remove the console? I tried popping out the ashtray but it's still not visible below it in the small opening.

I decided to order this kit from Suncoast , and connect it to a Pioneer AVH-P3400B, but did have a few questions for anyone that has used this kit: BTW I have the Bose System in my Cayman , and this kit seemed like the easiest way to keep the Bose AMP and Speakers (less wiring and hassle). The pictures of the kit show that it has 4 RCA cables, color coded, which appear to be FL, FR, RL, and RR - so I'm confused as to some messages I read that suggested Front/Rear fade does not work with this kit. Don't see a VSS on the HU and going to skip this. Okay. I see the HUD and MOST HUR both have this wire, so I'm unclear if that means I must simply splice/join them, or if I also need to run a wire to the parking brake too. I don't care about by-passing the parking brake. This is listed as MUTE on the HUD, but as "System Remote" in this article. Confused. I don't need the back up camera, and as far as I can tell I don't absolutely need this signal. I see the HUD and MOST HUR both have this wire, so I'm unclear if that means I must simply splice/join them, or if I also need to run a wire to a switched 12V source, and if so, what do others recommended?