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@ZuffenZeus apologies for the radio silence, life got in the way and couldn't get back to this topic.
Once again I opened the frunk and started looking for the DSP data line (black/red/yellow) and I wasn't able to find it. I took the following pictures to show what I found while taking things apart.
On #1 I stripped it all apart and couldn't find any cable that matched the DSP data line.
On #2 I stripped it all apart and found the following cables, which once again didn't match the DSP data line.
Please let me know your thoughts, and hope the following pictures help provide extra context.
Thanks!
Now that I've had time to think about your setup, I don't believe you're going to find the DSP line that is noted in Porsche technical instructions. Those instructions apply to the M680 HAES amplifier. Yes, it's confusing and Porsche doesn't really help with their limited installation and TSB information.
As you can see in the picture below, this is the more common Harman amplifier associated with the DSP option. You'll notice it has the 18-pin connector unlike your BOSE setup. Therefore, pinning the ground that is mentioned in the Porsche TSB, doesn't apply to your setup.
The best I can offer you is the schematic that I posted above to help trace lines. Are you still blowing fuses? Do you have the BOSE subwoofer behind the rear seats?
You are right! I have a 911 996.2 Targa from 2002 (MY2002).
From factory it has the following options:
- M662 (PCM 1 Porsche Communication Management screen with navigation, telephone module, radio, cassette player)
- M663 (Telephone handset for PCM 1)
- M680 (Bose sound system (analog))
- M692 (6-disc CD changer Becker Porsche CDC-3)
!
Where did you find these option codes that start with the letter "M"?
Here's my theory: You have options 662, 663, 680, 692, but none of them have "M" in front of the number. This originally confused me. The amp in the TSB is a HAES (Harman) M680 and applies to the technical instruction for getting the PCCM+ to work with those systems.
You on the other hand have the BOSE amplifier and if you remove it from the mount, you'll see this serial number and model information.
Last edited by ZuffenZeus; 06-03-2024 at 11:33 PM.
@wcytarga, the Porsche Loudspeaker ISO Harness 996-642-341-00 is suppose be like this. Plug A (Black / Chassis Side) directly into PCCM A. Plug B (Brown / Chassis Side) into Black Connector (Harness). PLUG C1 (Yellow / Chassis Side) into Red Connector (Harness). PLUG C1 (Yellow / Harness) into PCCM C1. I plugged C2 (Green) and C3 (Blue) into Red Connector (Harness) since I am not planning on using the CD changer.
I have a MY2002 CR-220 with BOSE ANALOG M680, non-DSP, non-MOST. I have PLUG A (Black), PLUG B (Brown), PLUG C1 (Yellow, only 1 wire connected, BK/RED for amplifier switch On/Off), PLUG C2 (GREEN), PLUG C3 (BLUE). wiring should be similar to yours since we share the BOSE ANALOG M680 regardless of stock headunit.
Just received the Porsche Loudspeaker ISO Harness 996-642-341-00, it did lower the gains and reduced the white-noise but it is still there even on mute and PCCM+ EQ had no effect on the subwoofer.
Without the Porsche Loudspeaker ISO Harness, very high gains, high white noise but the bass was manageable with the PCCM+ EQ. I honestly prefer the audio quality without the Porsche Loudspeaker ISO Harness but only if I can get rid of the white noise.
I gained a lot of information from these 996 PCCM+ threads. MY2002 is unique, a transition year. We don't have a DSP so there isn't a PIN 17 (DSP data line) to ground. We do have 2 amplifiers, main one which powers front and rear stage, "additional" amplifier which powers the subwoofer.
I am also wondering if we need to create a more substantial / direct ground for Plug Socket P1 (main amp) - PIN A (BRN) and Plug Socket K12A81 ("additional" amp) PIN A1 (BRN) to eliminate the white noise. This might not do anything for the subwoofer.
I went though all the secret menu settings and there isn't anything related to Subwoofer / Gain / Speaker-level / Line-level. I feel like this issue could be easily solved with software -- like a tune.
I am not sure on what to do next.
A. Direct Ground for both amplifiers -- this might solve the white noise but not the subwoofer issue.
B. Remove the Porsche Loudspeaker ISO Harness, buy 2x SPEAKER-LEVEL to IN-LEVEL ISO Adaptor and run them tandem (I couldn't find the post but this sounds promising)
C. Bypass Bose Amplifiers and run speaker output directly from PCCM+ to speaker by jumping Plug Socket P2 and delete subwoofer. @Body In White since you don't have an amp, have you found a resolution for the white noise?
D. Noise filters?
Thank you for the comment.
To ensure I don't blow more fuses when trying to follow your instruction, please let me know if the information on the following picture is correct.
Where did you find these option codes that start with the letter "M"?
Here's my theory: You have options 662, 663, 680, 692, but none of them have "M" in front of the number. This originally confused me. The amp in the TSB is a HAES (Harman) M680 and applies to the technical instruction for getting the PCCM+ to work with those systems.
You on the other hand have the BOSE amplifier and if you remove it from the mount, you'll see this serial number and model information.
Thanks for getting back to me!
You are right, I believe I saw M at the top and assumed all the codes included M . I got the following from my dealership (all the text is in Spanish, not really sure why):
In the time since I installed the PCCM+ in my GT3, I’ve seen a few other 996 GT3s with PCCM+ units and all of them have the white noise problem. For anyone reading this in the future with a GT3… I’m fairly convinced that this unit wasn’t designed with our cars in mind, it works, but… I suspect the PCCM Classic for the air cooled car would likely be a better choice for the 996s without factory amps.
Back to your question, I was going to try and build an appropriate noise filter, but honestly, the white noise is so faint that you can’t hear it once the car is on.
Thank you for confirming. I was thinking that the factory speakers are not compatible with the PCCM+ but I see that you upgraded your factory speakers as well so thought is a dead end.
I no longer think it is a factory amplifier or factory speaker issue. The PCCM+ seems to be better fitted for the MOST system. IMO, the PCCM Classic won't be a better fit, having the large Apple CarPlay screen is a game changer.
The white noise is faint with the Porsche Loudspeaker ISO Harness but the audio volume is also faint.
This will probably be on the back burner until it bothers me again... I will look into ISO Speaker Level to Line Level harness to try out.
Or... Option E - get a louder exhaust
Originally Posted by philPompili
I also have this issue. That little hiss when the car is quiet. I thought it was a faulty fan somewhere, but when I realized that it was coming out of he speakers. My car is a 996.2, non-Bose, that came with a single DIN radio. The previous owner had a single DIN Alpine deck (I didn't notice any hiss, but I only had it for a week or two before "upgrading")
It was probably there and you didn't notice.
Originally Posted by wcytarga
Thank you for the comment.
To ensure I don't blow more fuses when trying to follow your instruction, please let me know if the information on the following picture is correct.
@wcytarga Take a picture of the option label underneath the front hood. (looks like attached image below) This label will tell us everything we need to know about when it comes to your car.
Also, you never did answer my question... Do you have the BOSE subwoofer?
2004 MOST / BOSE 996 Cab. Installed PCCM+ in early 2022. Worked flawlessly for 2.5 years (I mean, sure, it reset the trip odometer).
In the past month or so, it has developed intense lag on all inputs: change the volume? Wait maybe 30 seconds for it to actually change. Lag is consistent on all inputs, except SIRI in CarPlay mode.
Also gets stuck in a reboot cycle that renders the whole thing useless. Reboot, load, reboot, load, reboot, load.
I did a factory reset that did nothing.
Thoughts?
The only clue is that the car has had a few other electrical gremlins over the past few months, which I am guessing is a failing ignition switch. Feels hard to connect those dots, but ignition switch (or battery) seems to be the root of most electrical issues...and I wonder if it could be mucking with the PCCM+ too.
I have the time synchronization set to GPS but at random it would get reset to the wrong time. Does this mean I need a software update? If so, is there any source that can provide this update? I did the install myself.
06-03-2024, 11:10 PM
. I got the following from my dealership (all the text is in Spanish, not really sure why):
