No sound from PCM

[Andy 997]

Hello folks. At the weekend i went out to the garage to start the car after a month or so of inactivity. Although i had connected the trickle charger, i had stupidly forgoten to switch it on. So of course the battery was completely drained. I switched on the charger and left it for 24hrs to charge the battery.
The car started first turn Woohoo!
But when i switched on the radio there was no sound. No radio, no Aux, no I pod. I reset the PCM by holding the ibfo button down for 10 secs, I reconnected my phobe to the car and called the wife. She got tge call but could not hear me, nor could i hear her, still no sound from the speakers.
This happened to me before and im sure there is a sequence of button presses i need to follow to solve this issue, but i cant remember what they are.
Can someone help an old forgetful 2009 Carrera S owner to get his Bose system going again. :dont know:

 

[Andy 997]

I think i will need to call Porsche and see if they can help. I have a trip booked at the end of the week and it would not be great if i cant have music. 😭😭, I hope its something simple. ☺

 

[jonno_]

That's an odd issue.

On the PCM2.1, holding down 1,4,8 keys together forces a PCM reboot.

Looks like there is a similar re-set for PCM 3.0 > https://www.youtube.com/watch?v=2ZZjRpdYaKo

 

[deMort]

Look under the driver's seat and make sure it's nice and dry there .. no water bottles etc .

I suspect that due to a flat battery it might need what we call a vehicle Handover .. this is kind of a reset but a bit different from the key press on the pcm.

This has to be done with a tester so indy/opc i'm afraid unless you have one yourself .

Various things like heated seats , mirror dipping inop after a flat battery and this will cure .. even door puddle lights inop .. fixed one of those today with a handover .

If that doesn't work i would be looking at swapping out the amp with a known good to confirm the amp has died .

Whilst they do die its normally due to water ingress though .

 

[Andy 997]

Thanks for the replys, I did try the PCM 3 factory reset and the vehicle handover reset, but no joy im afraid. Will check for dampness tomorrow, I might try dissconnecting the battery for an hour to completely drain the systems. Then try reconnecting. Im thinking that maybe the battery wasnt complettely flat and was still providing a few volts to the systems, this may have confussed it all and a hard reboot might do the trick. c: