PCM1 CD changer plug - where is the anti-shock control?

Hi everyone, I have just switched the input plug for my cd changer and added a 3.5mm jack input to the CD changer socket on the PCM1 on my 2002 996 Carrera 2 using one of these cables from eBay. http://www.ebay.co.uk/itm/Blaupunkt-Aux-IN-Input-I ... Works a treat and I can now plug into my phone and listen to music from that on the CD channel and it only cost £5. I am planning to get a cheap bluetooth receiver from amazon and wire this in to get bluetooth stereo connection. I already did this on my landrover and the total cost was £15. The only issue is when I go over bumps the audio momentarily drops out which i think is down to the anti-shock from the cd changer which is still running telling the head unit to mute. Does anyone know if my assumption on the audio dropout is correct and if so is it possible to disable this anti-shock functionality? Are any of the wires in the other CD changer input plugs (yellow and green) responsible for this? I tried unplugging the green plug, but the PCM then says no cd changer and I don't get any audio. The CD changer input (plug c) consists of three coloured connectors - blue which is the one I changed, yellow and green. The pins are as below: Plug C 1 - Lineout, rear left 2 - Line out, rear right 3 - AF ground 4 - Line out, front left 5 - Line out, front right 6 - Terminal 30 for amplifier 7 - Control lead for CD changer 8 - Terminal 30 for CD changer 9 - Free 10 - Data lead 11 - Clock lead 12 - Reset lead 13 - Free 14 - Free 15 - Free 16 - Free 17 - Free 18 - CD AF, ground 19 - CD AF, left 20 - CD AF. right Note Plug C consists of 3 parts. Pins 1 to 6: yellow housing. Pins 7 to 2: green housing. Pins 13 to 20 : blue housing. Pins 1 to 6 are the loudspeaker outputs to the amplifier. They are assigned only if an amplifier is installed. Pins 7 to 12 are the control leads for the CD changer. Pins 18 to 20 are the loudspeaker outputs of the CD changer. Pins 7 to 20 are assigned only if a CD changer is installed.

I don't think their is an anti shock control to the head unit as you describe. I think it is all contained in the changer and if it detects a shock then it just cuts the audio output for a split second. I think your problem lies elsewhere, maybe a loose connector into the back of the PCM unit.

I think if i understand it right you have unplugged the cd changer and fitted this new lead so isnt the cd no longer connected to the pcm ? Pict here shows the wireing .. http://www.911uk.com/files/2002_pcm1_with_bose_car_loom_118.jpg There is no anti shock , the cd changer is internally mounted on rubbers to dampen out shocks AFAIK. Rule of thumb i was taught many years ago ... did it do it before you touched it , yes then its a fault , no and its something you did . poor connection seems the most obvious atm but the pict above may help you.

Hi Neilos, can you let me know which cable you purchased please as I would like to do this mod. I can let you know if I have the same issue once I install it.

Thanks for the replies, the blue section of the yellow/green blue combo plug is what I changed - (see link to eBay in original post gc99364) I would think that if it is a loose connection then it should drop audio when on radio over bumps which it doesn't. This is the second of this type of mod I did, the first one was to plug a phono to jack into the lead that takes the audio from the cd changer in the luggage compartment and feed through the bulk head into the glove box. It did the same audio drop out then and then I bought the cable from eBay - and installed this way as its a bit of neater job and I hoped it might cure the audio drop out on bumps. Its much easier to route the cable from the back of the PCM this way, behind where the cigarette lighter socket is there is a hole through which you can feed the wire through the the hole in glove box where the lights fits. I'll investigate the leads/plugs from the cd changer to see if I disturbed anything when I did the first mod that might be causing this.

Only other thing i can think of is the speed of data transfer is faster with the phone than the cd but that would cause random drop outs not over bumps.

Hi got my cable and installed it - no cutting out over bumps however do get a momentary pause when the CD changes tracks with certain CD's inserted. Early days but seem to have got around it using CD burned without gaps. Also if you click scan the CD is paused and no issues but you would need to do this each time the car is started. Burning a CD with one track filling the CD will be my next resolution if I do find I have further issues. Not sure if this helps you but cheers for the link to the cable and the idea!

Aux audio still cutting audio over bumps Hi All After giving up on this issue for the past couple of years while the car hasn't really been used I have come back to it and i'm still stumped. It definitely something to do with the CD changer as when I am playing music through the aux cable and I tap on the CD changer the audio drops out. It must be one of the cd changer data connections in the green section of the connector that is doing this. Perhaps my suspension is a bit older/creakier that yours @gc99634. The fact that yours pauses between tracks shows that one of these data connection cables has the ability to do this. Out of interest do you have the BOSE amp? Could this be something to do with it? I have disconnected each of the data cables in turn from the green connector to see if I can isolate which one it is, but each time I disconnect one the PCM unit says no CD player connected. Next steps for me are: 1. burning a one track CD 2. Looking for loose cables on the cd changer 3. Binning the PCM and installing a new modern double din.