Hi all, I recently bought a 996 Turbo and have been thoroughly enjoying all aspects of it bar 1 - the woeful stereo system! I know I know - I should be listening to the music of the flat 6, revelling in the acceleration and handling etc but living just outside London I inevitably spend time in traffic hoping to find open roads and music is a necessity to maintain some sanity!
My car is a 2003 with Bose, CDR23 (single DIN CD head unit) and CD changer in the boot, so has the MOST fibre optics bus which adds some complexity. My aim was to swap out the head unit with an iPhone compatible double din unit, remove the Bose amp and CD changer and install a 5 channel amplifier. A key factor was to be able to revert the system back to standard so no cutting of wires in the factory loom.
I bought the following:
Pioneer App Radio 2 (SPH-DA100)
Kenwood KAC-X5D 5 channel amp - very compact and not overly expensive
Connect2 CT23PO02 fascia kit
Autoleads PC2-95-4 wiring loom
Autoleads PC5-100 car aerial fakra adaptor
2x 5m shielded RCA cables (one with built in remote lead)
HVAC surround piece for lower console - Porsche part 996 552 339 00 01c
I then worked through the wiring diagrams to identify what is present in the existing looms and what needed altering. For the head unit the missing connections are illumination (dimmer) and 12v switched. At the amp end, the PC2-95-4 allows you to connect straight into the car loom from the amp for speakers, earth and permanent power but I opted to run separate earth and perm 12v connectors to prevent any risk of overloading the standard wiring.
My wiring table was as follows:
Once I had modified the PC2-95-4 loom by soldering in additional speaker wiring, upgrading the sub connections and removing unused wires it was time to start removing interior panels. I'm not going to describe how to dismantle the interior as it is all well documented on various forums but feel free to contact me if you want any advice.
I already owned the stereo removal keys for the CDR23 as they match the Audi factory stereo which I removed in my old RS6 so the CDR23 was removed and disconnected without a problem. My car came with a Nokia bluetooth hands free kit so that was also removed and wiring reverted back to standard.
Having done several audio installs over the years in previous cars I had a spare couple of ISO harnesses - these were sacrificed to provide the 12v switched and illumination mini female connectors that I inserted into the 911 ISO connector slots. The 911 ISO connector has a small yellow tab that must be unlocked and slid out to free the pins so you can add in additional mini iso connectors.
Next the HVAC controls were removed ready to move them down to the lower console bottom slot - the wiring access behind the console is restricted so take your time threading the wiring harness down! The controls simply slot in but mine was a tight fit, then the purchased trim ring just clips on over the top to cover the edges and profile to the lower console.
For illumination, I tapped the cigarette lighter illumination feed which is easily found using a multimeter. It is the blue/white lead in this picture:
And for switched live someone had mentioned finding a source in the HVAC loom so having confirmed earth and perm 12v the switched live does exist at the opposite end of the black HVAC connection - blue/black wire furthest left of this picture:
Fascia fitting - the Connect2 metal frame is ok but I found my Pioneer supplied cage provided a better fit to the dash frame. I took quite some time with a Dremel filing down the 911 dash frame to ensure a flush cage fit, used sections of an old license plate as wedges (perfect thickness doubled up) and a couple of screws to hold everything tightly. I also needed to remove the riveted in metal wings behind the dash cage on a separate metal frame - again, time and patience is key. The black pastic Connect2 fascia has 2 lips behind it and I needed to again dremel down the depth of the inner lip as it was contacting the head unit and pushing the fascia out by 2-3mm meaning it was not flush with the dash.
Finally achieving a decent flush fit I wired up the stereo with all connectors, wired in the hands free microphone, hooked up the handbrake switch and ran the RCA leads into the drivers side footwell. It was then a case of testing the unit for power, radio reception (no audio yet) and iPhone connectivity - all good.
Bose sub rewire:
I did not take any pictures of this but it is very straight forward. Pop the rear seats down, remove the trim rings around the sub ports and undo the Torx screw behind here. The sub then slides forwards, rotate it when it can go no further and disconnect the sub connection at the rear. You can then lift the sub out of the car.
Rewiring is required as the subs are 1 ohm impedence and run in parallel. Remove the 20+ torx screws around the outside of the box and simply rewire the subs to be in series (2 ohm) which is within my Kenwood amp specs.
Reassembly is the reverse of removal
Amplifier Install:
Having removed all the trim panels in the boot and removing the Bose amp and CD changer I worked out that the Kenwood amp would fit very neatly within the CD changer bracket. The changer bracket slots into 2x metal clips at the bottom (under the brake master cylinder) and uses a single bolt at the top to fix it in place. I straightened out and cut (good old Dremel again) the changer bracket so that it is a vertical sheet and moved one of the original changer clips so that the bracket would drop straight into the clip vertically while still using the bolt at the top. A couple of additional holes in the bracket and I bolted the amp straight on.
I moved the amp wiring loom up and cable tied it to a couple of convenient slots, then connected and secured the PC2-95-4 loom around the bulkhead:
Then I ran a dedicated fused power through from the battery to the amp location and the RCA leads. To get the RCA leads through from the drivers footwell into the boot, I used the grommet just behind the battery... Thinking I would just punch a whole straight through the grommet, I promptly pushed the grommet straight into the car (i.e. it popped out completely). With it out, I drilled a hole through the grommet and fed the RCA leads through then attempted to reseat the grommet - this was a major pain in the ar$e! There are 2x hoses just in front of the grommet opening (battery removed) and I ended up spending about an hour performing key hole surgery to reseat the grommet back in its place. :frustrated:
In this picture, you can see the amp secured in place mounted to the changer bracket:
While this picture shows the space you have to work with and the clip that I have moved:
And here is the amp with all trim pieces back in place:
And for reference, here are a couple of shots of the Bose amp wiring connector:
Overall I am very happy with the results - sound quality is much improved and the dash has been brought up to date. The App Radio is probably the weakest link, it works reasonably well but has a few quirks where you have to select things on both the head unit and the phone but I paid <£200 for it (Halfords deal and Quidco combination) so it hasn't set me back too much...
Hopefully this may be useful info for people in the future! :bye:
Ross
My car is a 2003 with Bose, CDR23 (single DIN CD head unit) and CD changer in the boot, so has the MOST fibre optics bus which adds some complexity. My aim was to swap out the head unit with an iPhone compatible double din unit, remove the Bose amp and CD changer and install a 5 channel amplifier. A key factor was to be able to revert the system back to standard so no cutting of wires in the factory loom.
I bought the following:
Pioneer App Radio 2 (SPH-DA100)
Kenwood KAC-X5D 5 channel amp - very compact and not overly expensive
Connect2 CT23PO02 fascia kit
Autoleads PC2-95-4 wiring loom
Autoleads PC5-100 car aerial fakra adaptor
2x 5m shielded RCA cables (one with built in remote lead)
HVAC surround piece for lower console - Porsche part 996 552 339 00 01c
I then worked through the wiring diagrams to identify what is present in the existing looms and what needed altering. For the head unit the missing connections are illumination (dimmer) and 12v switched. At the amp end, the PC2-95-4 allows you to connect straight into the car loom from the amp for speakers, earth and permanent power but I opted to run separate earth and perm 12v connectors to prevent any risk of overloading the standard wiring.
My wiring table was as follows:
Once I had modified the PC2-95-4 loom by soldering in additional speaker wiring, upgrading the sub connections and removing unused wires it was time to start removing interior panels. I'm not going to describe how to dismantle the interior as it is all well documented on various forums but feel free to contact me if you want any advice.
I already owned the stereo removal keys for the CDR23 as they match the Audi factory stereo which I removed in my old RS6 so the CDR23 was removed and disconnected without a problem. My car came with a Nokia bluetooth hands free kit so that was also removed and wiring reverted back to standard.
Having done several audio installs over the years in previous cars I had a spare couple of ISO harnesses - these were sacrificed to provide the 12v switched and illumination mini female connectors that I inserted into the 911 ISO connector slots. The 911 ISO connector has a small yellow tab that must be unlocked and slid out to free the pins so you can add in additional mini iso connectors.
Next the HVAC controls were removed ready to move them down to the lower console bottom slot - the wiring access behind the console is restricted so take your time threading the wiring harness down! The controls simply slot in but mine was a tight fit, then the purchased trim ring just clips on over the top to cover the edges and profile to the lower console.
For illumination, I tapped the cigarette lighter illumination feed which is easily found using a multimeter. It is the blue/white lead in this picture:
And for switched live someone had mentioned finding a source in the HVAC loom so having confirmed earth and perm 12v the switched live does exist at the opposite end of the black HVAC connection - blue/black wire furthest left of this picture:
Fascia fitting - the Connect2 metal frame is ok but I found my Pioneer supplied cage provided a better fit to the dash frame. I took quite some time with a Dremel filing down the 911 dash frame to ensure a flush cage fit, used sections of an old license plate as wedges (perfect thickness doubled up) and a couple of screws to hold everything tightly. I also needed to remove the riveted in metal wings behind the dash cage on a separate metal frame - again, time and patience is key. The black pastic Connect2 fascia has 2 lips behind it and I needed to again dremel down the depth of the inner lip as it was contacting the head unit and pushing the fascia out by 2-3mm meaning it was not flush with the dash.
Finally achieving a decent flush fit I wired up the stereo with all connectors, wired in the hands free microphone, hooked up the handbrake switch and ran the RCA leads into the drivers side footwell. It was then a case of testing the unit for power, radio reception (no audio yet) and iPhone connectivity - all good.
Bose sub rewire:
I did not take any pictures of this but it is very straight forward. Pop the rear seats down, remove the trim rings around the sub ports and undo the Torx screw behind here. The sub then slides forwards, rotate it when it can go no further and disconnect the sub connection at the rear. You can then lift the sub out of the car.
Rewiring is required as the subs are 1 ohm impedence and run in parallel. Remove the 20+ torx screws around the outside of the box and simply rewire the subs to be in series (2 ohm) which is within my Kenwood amp specs.
Reassembly is the reverse of removal

Amplifier Install:
Having removed all the trim panels in the boot and removing the Bose amp and CD changer I worked out that the Kenwood amp would fit very neatly within the CD changer bracket. The changer bracket slots into 2x metal clips at the bottom (under the brake master cylinder) and uses a single bolt at the top to fix it in place. I straightened out and cut (good old Dremel again) the changer bracket so that it is a vertical sheet and moved one of the original changer clips so that the bracket would drop straight into the clip vertically while still using the bolt at the top. A couple of additional holes in the bracket and I bolted the amp straight on.
I moved the amp wiring loom up and cable tied it to a couple of convenient slots, then connected and secured the PC2-95-4 loom around the bulkhead:
Then I ran a dedicated fused power through from the battery to the amp location and the RCA leads. To get the RCA leads through from the drivers footwell into the boot, I used the grommet just behind the battery... Thinking I would just punch a whole straight through the grommet, I promptly pushed the grommet straight into the car (i.e. it popped out completely). With it out, I drilled a hole through the grommet and fed the RCA leads through then attempted to reseat the grommet - this was a major pain in the ar$e! There are 2x hoses just in front of the grommet opening (battery removed) and I ended up spending about an hour performing key hole surgery to reseat the grommet back in its place. :frustrated:
In this picture, you can see the amp secured in place mounted to the changer bracket:
While this picture shows the space you have to work with and the clip that I have moved:
And here is the amp with all trim pieces back in place:
And for reference, here are a couple of shots of the Bose amp wiring connector:
Overall I am very happy with the results - sound quality is much improved and the dash has been brought up to date. The App Radio is probably the weakest link, it works reasonably well but has a few quirks where you have to select things on both the head unit and the phone but I paid <£200 for it (Halfords deal and Quidco combination) so it hasn't set me back too much...
Hopefully this may be useful info for people in the future! :bye:
Ross