997.1 Speaker wiring question
11-11-2015, 07:34 PM
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997.1 Speaker wiring question
I am new here and have searched the forums but cannot find the answer I am looking for.
I have just bought my first 911, a 2005 (2006 MY) 997. The radio/CD does not work i.e. no sound can be heard at all, no crackle, static or anything just complete silence. After much reading and investigation I have ascertained that the car has a PCM 2.1 unit with no navigation and no telephone. It does not have a BOSE system but does have an ASK amplifier. It also has a multi-CD changer connected via an optical lead (MOST I think it is called) but the amplifier is connected by conventional wiring.
My understanding is that the amplifier ONLY feeds the two front door speakers and the centre speaker and that the remaining speakers are fed directly from the PCM.
In correspondence with a guy in Norway (I am in the UK) who repairs the ASK amplifiers he tells me that with the amplifer disconnected I should still get some sound from the radio from the speakers not fed by the amplifier. If I got no sound then it pointed to a problem with the PCM. This was the conclusion I came to.
I removed the PCM and took it to a well known and highly regarded company here in the UK. I took it to them yesterday and in the afternoon they telephoned to say there was nothing wrong with the unit. They did say that their charge was £75 + tax (20%) for diagnosis but that the charge was deducted from any repair cost should I get them to repair it. I was convinced the PCM was at fault so went ahead. I am annoyed that my analysis was apparently wrong and I have just spent £90 for nothing.https://rennlist.com/forums/graemlins/banghead.gif
The unit still emits no sound when fitted to the car. So the problem must be between the PCM and the speakers.
Looking at the wiring I have four pairs of speaker wires which plug into the PCM and four pairs of input wires to the ASK amplifier. So by deduction if some of the speakers are fed directly from the PCM there must be somewhere where the speaker wires from the PCM are split to feed both the amplifer and the directly fed speakers.
My question is where?
I intend upgrading to a combined radio/mp3/nav/telephone unit but want to a) first get the system working and b) make sure the PCM works in order to refit it when eventually I sell the car.
Any suggestions or thoughts gratefully received.
Thanks.
I have just bought my first 911, a 2005 (2006 MY) 997. The radio/CD does not work i.e. no sound can be heard at all, no crackle, static or anything just complete silence. After much reading and investigation I have ascertained that the car has a PCM 2.1 unit with no navigation and no telephone. It does not have a BOSE system but does have an ASK amplifier. It also has a multi-CD changer connected via an optical lead (MOST I think it is called) but the amplifier is connected by conventional wiring.
My understanding is that the amplifier ONLY feeds the two front door speakers and the centre speaker and that the remaining speakers are fed directly from the PCM.
In correspondence with a guy in Norway (I am in the UK) who repairs the ASK amplifiers he tells me that with the amplifer disconnected I should still get some sound from the radio from the speakers not fed by the amplifier. If I got no sound then it pointed to a problem with the PCM. This was the conclusion I came to.
I removed the PCM and took it to a well known and highly regarded company here in the UK. I took it to them yesterday and in the afternoon they telephoned to say there was nothing wrong with the unit. They did say that their charge was £75 + tax (20%) for diagnosis but that the charge was deducted from any repair cost should I get them to repair it. I was convinced the PCM was at fault so went ahead. I am annoyed that my analysis was apparently wrong and I have just spent £90 for nothing.https://rennlist.com/forums/graemlins/banghead.gif
The unit still emits no sound when fitted to the car. So the problem must be between the PCM and the speakers.
Looking at the wiring I have four pairs of speaker wires which plug into the PCM and four pairs of input wires to the ASK amplifier. So by deduction if some of the speakers are fed directly from the PCM there must be somewhere where the speaker wires from the PCM are split to feed both the amplifer and the directly fed speakers.
My question is where?
I intend upgrading to a combined radio/mp3/nav/telephone unit but want to a) first get the system working and b) make sure the PCM works in order to refit it when eventually I sell the car.
Any suggestions or thoughts gratefully received.
Thanks.
