Retaining "key sense" with aftermarket head unit install

Disappointed with the nearly useless CDR-30 unit in my 7 CS I had an Alpine double DIN headunit installed by a local, very reputable dealer. But for the poor tuner performance (due to the lack of a real antenna on the Cayman ) it all works well, with integrated BT, iPod , etc., except for the fact that I've lost the "key sense." Modern Porsches, like many other cars, don't have accessory positions for the keys anymore. In the Cayman , the stock head unit would continue to be powered after you turned the key off, and would shut off either through manually turning it off, or by opening the door. This is a great feature, and a very useful one. Unfortunately, despite having the Nav.tv component installed, which helps keep the aftermarket head unit working with the MOST Bus and PCM components, the only way I can keep the head unit powered on is to have the key in the "run" position. I'm not a big fan of this. My installer found a component that was supposed to fix the problem, but they installed it and it only kept the head unit powered for 25 seconds before shutting off power. Has anyone else figured out a solution to this problem? I know there are plenty of us with non-OE head units. It's hard for me to believe we're all leaving our keys in the "run" position in order to listen to music without the engine running. -tj in los gatos

You had a CDR30 in an '07? Anyway there is a programmable relay made by PAC (model TR-7). The shutoff delay can be set up to 4:15 min/secs. I'm suprised they didn't use it (or if they did, they didn't program it correctly. It's only about $20. Not sure why you need to be in the run position, just inserting the key powers all accessories in my Gen2. Are Gen 1's different? Are you sure they didn't run the red (trigger) wire from the wrong place (where it only gets power in "run"?

Apologies, and good catch. A CDR-24, not a CDR-30 . = ) I don't know why I need to be in the run position either, but nothing powers up when I insert the key. I think that's what they call "key sense." I'll tell them about the part from PAC. I trust this place implicitly, they've done lots of modern Porsches, BMWs, and others, and know what they're doing. Thanks for your help! -tj in los gatos

It depends on how the "keyed" power was done by your installer. When I did mine I used a fuse tap on on position C6. It unfortunately, does exactly as you described. It only powers in run mode and not in accessory mode when you insert the key. So after doing some research, I found that the fuse at position B9 (used for telephone accessories) will activate/deactivate when inserting or removing the key. I moved my fuse tap to this location and it works!

Yes, I used B9 also.

Excellent! Thanks guys. I assume that the "open door to shut off the head unit" feature is lost. -tj in los gatos

Possibly the PAC TR7 can be used to do something like that. It's a very programable controller. However, it is complex, so I recommend it only for those fairly experienced with electronics. The manual is available on-line. http://www.pac-audio.com/PACProductData/TR7/1_Instructions/tr-7_instructions_010505.pdf

By the way, do you have a photo of where this wire is, or how I get to the B9 fuse position? Is it just behind the kick panel trim or did you tap in to it at a different location? Do you know what color the wire that I'm looking for is? -tj in los gatos

You use something like this: (make sure you get the one for the right fuse size) Amazon.com: ATM Add-A-Circuit (same function as Bussmann BP/HHH), ATM Fuse Tap: Musical Instruments Crimp your red wire from the radio to the end and then plug it in to B9. Why don't you have your installer do it since he's the one who f'd up. It'll probably require removing the radio anyway if he just taped in somewhere under the dash. My guy fished the wire down behind the carpet and into the fuse-box, so with the cover on, it looks stock.

I have the same issue with my recent aftermarket head unit install. I have a 2009 Boxster with 6 speed and B9 is open with only one metal prong in the slot. I tried several other fuse locations after reviewing the fuse location booklet with no success. Any suggestions? Thanks, Jim

Not sure what you mean "one metal prong in the slot". Is there something stuck in that location? One tab of a fuse? Is there anything attached to the prong?

The B9 slot is unused and only has one instead of two metal prongs where the fuse would push in to make a connection. I looked at the other unused fuse slots and they were the same. Thanks Jim

OK, I would call those contacts, not prongs. I just checked mine - it's the same (2010 MT). It will work. The 1 set of contacts is the "hot" side (switched +12V). If there was an accessory being powered by that fuse, there would be a return contact pair on the other side. One good way would be be to splice in to your unit's power wire an inline fuse, then just use a spade connector on the end and plug it into the hot side of B9. Or use the add-a-fuse pigtail that I linked to earlier. However, that isn't really necessary since it is designed (as it's name implies), to add another fused circuit in parallel to it's host circuit.

That sounds like it will work and I will try it tomorrow.:thanks: Thanks alot for your help. Jim

Success! I checked the B9 single contact with my voltmeter and it showed 12V when the key was in. I then soldered a small wire from both sides of the 7.5 amp fuse and tested the head unit with success. Next will be to install an inline 7.5 amp fuse per your recommendation. Thanks again:dance: Jim

This is the inline fuse I just installed to the B9 and it works like a charm with my six speed 2009 Boxster . Jim

Excellent! Now enjoy! Did you have any problem fishing the wire down the footwell behind the carpet and into the fusebox? I wasn't watching very closely when Loi did mine. I think he partially removed the carpet where it tucks behind the door trim. What head-unit did you install? Did you use the Euromotorspeed kit?

I used Loi's install kit and I took out all the Bose stuff except for the 7" door speakers. They are really shallow but appeared decent quality. The head unit is the Pioneer avic z140bh and amp is the JL 600 (I believe) that is 5 channel X 100 watt class D. I replaced the dash tweeters with Focal and rebuilt the Bose rear box with a 5.5" Focal component speaker set. It sounds awesome but the bass can be a bit light with the top down. I decided to not put in a sub at this time. Loi was great when I called with a few questions. I emailed him this fix for future customers. The install looks factory. Thanks Jim

Old post but has anyone else had an issue using the B9 slot? I get power when the key is inserted but after approximately 15 seconds I get no sound from the speakers. The headunit is still powered. Removing the key and reinserting will repeat the process. I am back to using the C6 slot until I can find a better one. Car is a 2007 CS w/ BOSE using the NAV-TV 997HUR to an apline headunit. Also, on my car the B9 slot has a 7.5 amp fuse.

I have a 2006 CS w/ Bose , and I'm pretty sure it was B9 worked for me. See the pic in my install thread: https://www.planet-9.com/987-cayman...man-and-boxster-electronics/200065-2006-cayman-bose-complete-gut-replace-2.html

Yeah I was just curious if anyone else ran into the same issue I had with B9, with the sound cutting out. It's a strange issue and I have no idea why it would happen. I'd much prefer to power the stereo from that location (or another that has power when the key is inserted)

My mistake, I misread it that you were getting nothing, but now I see the head unit was still powered on and just the sound cutting out...

Sounds like the HUR or BOSE fiber amp is not getting power after that timeout. Is the MOST-HUR powered by the same constant and switched sources as the head unit?

I'm fuzzy on what I did now lol but I definitely took power and ground from the subwoofer harness since some previous a-hole cut the wires off the harness so I just made do with what was available. I'm sure that the amp powers off after 15-20 seconds which is why I ended up losing sound even though the headunit stayed on. Oh well, it's not a big deal really.

I know this is an old post/thread but I've just installed a new head unit ( Kenwood ) which has a trigger lead also. I tied the trigger wire for ACC from the HUR unit to the trigger wire on the head unit. At first this wire tapped into a lead from the fuse block, the wire was located behind the carpet/kick panel. This gave me no power once the key was in the off position and the key was still inserted. I used this thread and located the wire (orange) from the row Bf9 position. This worked as I wanted it to, but after a period of time it shut off. I was hoping I would get a true ACC position off of the key. I did not want to used the add circuit method because I didn't want to tap into fuses and leave wires crossing over other fuses. I did quite a bit of research from the wiring diagrams download (this was a pia because they are not true PDS structure and you can't use the find command in the reader. I'm still looking for a true ACC solution, but this will work for now. Oh buy the way, I'm looking for this solution so I can listen to music while waiting in the parking lot for the grandson to get out of school, or any wait for that matter. Thanks,