North Shore 911

Jumping into my 2010 997.2 Cab this afternoon I was unpleasantly greeted with no sound from my Bose stereo. Other than no sound, everything works fine: my iPhone phone pairs fine, I can see and select different radio stations, I see options for choosing different audio inputs, etc., it’s just that I don’t get any sound from any source. I’ve never had this happen before, so before I start pulling fuses I thought I’d seek the collective wisdom from this crowd first.

In doing a quick search on the interwebs, it appears that some folks have solved this with checking/pulling/replacing fuses, while others seem to have solved it with a mysterious combination of turning the car on and off with the radio on and off and locking and unlocking in a certain pattern. Others seem to point to a crimped optic cable or a bad amp. Before I start my own diagnostic exercise, does anyone have any high-probability solutions?

TIA for any help on this!

Petza914

Not an S, so no Bose? Sounds like your amp has failed. Might have a fuse on it you can check and try to disconnect the battery for 10 minutes to see if the amp will reset.

North Shore 911

Sorry, it's a 4S with Bose .... I am going to pull the fuses in the panel this morning (slot D10 I think) to see if that jump starts it since a PCM reset didn't work yesterday afternoon... Any additional thoughts on potential easy fixes before I head to my indy...?

Petza914

I'm not sure if the stereo setup in the .2s is very different from the .1s or not - Bruce would know - but if the Bose amp has failed, you should still get low booming sounds from the subwoofer as that takes a clean signal and has it's own amp (at least it does in the coupes). If you have zero sound including no low frequency, that's usually a PCM unit itself failure.

Bruce In Philly

Maybe.... There is a bit of mystery to the .2 amp. The amp, located under the passenger seat does many different functions. It decodes the digital signal from the head unit and processes it into stereo, 5.1, or whatever format comes into it. If not 5.1, meaning the rear sub woofer does not have its own distinct signal, it synthesizes one... then sends it via fiber optic cable to another amp/processor in the rear for that sub woofer. So...... if the amplifier section failed, then you would hear the subwoofer only as the digital section is still working. If you get nothing, no sound from the sub as well as any speaker, then maybe the entire amp failed (whatever that means). Or, the head unit is just not sending a signal to that amp/processor so it is sit waiting to hear something.

Try this.... with the unit on, press and hold the INFO button... just hold it in... this will reset the unit. The memory will not be wiped. Easy try, and better than disconnecting the battery. Then, check the fuses. Then, with the unit on, disconnect the fiber cable from the amp and check to see if it is lit... you will see red(?) light coming from it.. it will be obvious. That may tell you something. If dark, the problem is in the headunit. If on... it may not be sending a signal on the light pathway. I don't know if you can disconnect the fiber connection without removing the amp.... I removed the amp first then the cable but I was trying to trouble shoot the amp section. The big connector is fiddly to lever off but you can do it.

Other than that, I would not know what to do. Check for codes? There does not appear to be an indicator, like an LED on the amp to show that it is on and working.

Lotsa spectulation here. I am not sure what an indy can do except read the codes. I am not sure what a dealer can do either unless they have some sort of trouble shooting guide to follow... I never heard of that but maybe.

Please post what you find... we can all learn from this as these units age.

Peace
Bruce in Philly (now Atlanta)

Wayne Smith

Yes, please keep us updated. There are a lot of unknowns regarding the failure mode (or modes) in this circuit.

North Shore 911

Thanks Bruce, these are wise words. First update:

• It's not the fuses
• A "soft" PCM reset (holding down the "Info" button) didn't change anything
• A "hard" reset via the PCM reset option also didn't change anything
• The battery is fine (I had hoped the battery was on its last legs and began to shut down the ancillary systems, but that was a dead end...)

So before I pulled the optical cable from the amp I headed over to my indy who just bought the new PIWIS 3 to have him scan the car for faults. What came up was a fault in the MOST system, so since that's super-generic we'll need to use some loops to isolate the individual issue. Bummer, but that will take some trial and error time to find the underlying fault. Hopefully it's just a pinched optical cable and not a toasted PCM, but I'll let you guys know where I land on this after I drop off the car next week. In the meantime, I'm thoroughly enjoying the sound of shifting at 6k with the full-throated exhaust sound of PSE On + Fabspeed sports headers . So losing Pandora isn't all bad ....

Bruce In Philly

Pandora? Are you using the Apple hookup? Any aftermarket products? First disconnect all of these, then follow the reset procedure.

Peace
Bruce in Philly (now Atlanta)

BHMav8r

mine doesnt work if it gets below like 50 degrees. go figure.

looking at replacing the head unit this fall

plz keep us updated

YungPorsche

This is my post inauguration, so be gentle.

I'm having the exact same issue as you. Did you ever find the issue and resolve it? If so, what was the problem? Thank you in advance. Really appreciate your time.

richard788

I'm having the exakt issue in my 2009 987.2 Cayman with PCM 3.0 and Porsche Sound Package Plus. In fact I have ZERO audio in the car - even the sensor warning when reversing is muted!

* There is no optical cable in Sound Package Plus so I guess I can't check if lights "flows" into the amp in order to make sure the fault is not in the PCM.
* After talking to renowned Norwegian amp repair service https://www.bergvillfx.com I learned that the amp merely drives 3 speakers. The base in the doors and the centre speaker under the windscreen.
* This leads me to believe that there is no fault of the amp's part, as all speakers are dead. Rather the fault lies inside the PCM 3.0 itself.
* The PCM works flawlessly except the fact it does nt produce any sound.
* This means option for now is to buy an upgrade kit for PCM 3.0 as the fault is most likely in the PCM unit itself. Example: https://rennlist.com/forums/997-foru...d-carplay.html

Anyone having experienced a similar challenge?