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Will you be making your harness available for purchase? I bet many would purchase it. I would.
thanks
Bennett
yes - i want to test the backup harness first with a video to showcase how it all works b4 selling it. id rather cover my bases.
the other one re the RCA output i stated in my post when taking apart the porsche mostHur adapter - is that its not true 4 channel output, and that the fader function is via an emulated system.
i am not sure if anyone would want a 2 channel stereo RCA output, as the pccm+ essentially is 2 channel (stereo) output only from the 10pin audio harness - like 100% of all android / aftermarket stereos (at least when attached to a fibreOptic box). it is not true 4 channel output.
if anyone is interested in the backup camera harness - PM me.
Traditionally isoConnector A is never used for audio transmission, it is used for power, gnd, antenna accessory power. On the oem isoConnector A, it will normally also include reverse cam trigger (pin 19 when purchaed), microphone (pins 8+9 when telephone accessory is purchased), 2 wakeup pins (4 + 20 gateway + and module I cant recall). Also the 2 CAN (hi+low) pins (normally 1 + 2) u mention is for digital canbus data (such as primary reverse trigger, parking brake engagement, headlamp illumination, helping regulate on + off, sleep mode type of stuff). Where did you get your isoConnector A pin-outs. Id love to see that chart as I can tell it has changed from the pcm 2.1 configuration ... but even on the pccm+ isoConnector A you mention, we are looking at L + R (2- channel only) as the other 2 you mention are canBus signals.
Now from the 12 pin audio connector going to the most box... it isnt 4 channel output at all (but perhaps someone with electronics background can prove me wrong). i posted everything in the previous post with photos - taking the mostUnit apart, even the harness and also cross referencing the pin readOut.
There is L + R channel, but the TX + RX are not rear analog outputs - they are digital transmission + receiver signals... and become cross-linked (ie RX goes into the TX channel and vice versa). I suspect they are used to calculate the front / rear ratio to create a digital the fader effect .... this is an emulated system to give the illusion of 4 channel output - when in is from a true L + R stereo only (2 channel) output from the pccm+. I was surprised to realize there is no true 4 channel output whatsoever when running bose.
The other dead giveaway (on top of the circuit board labels) was when I took apart the harness itself, the extra special shielding and grounding (to help preserve the analog audio signals) covered up two wires ONLY (L+R green/white) to the mostHur box (but not 4).
Originally Posted by svandamme
Isn't there there 4 channel Line out on the DIN connector???
Connector A
C2 Line OUT FR Front Right
C15 Line OUT FL Front Left
C1 CAN L Line RR Rear Right?
C14 CAN H Line RL Rear Left ?
That suspiciously looks like 2 channels, no?
Not sure what the CAN L or CAN H implies, but the RR and RL seems correct?
And its not the powered line either, those are B1 to B8
I haven't seen anything specific to my current, pre-install configuration, but I imagine that I'm not alone. I'm trying to determine how to feed an aftermarket amp with a signal from the PCCM+. I removed my original ASK amp (non-BOSE system), spliced into the factory harness to complete my aftermarket setup. BUT the current aftermarket head unit has RCA outs to send the line-level signal to the amp ... PCCM+ does not. I would need to know which pins on the back would send this signal. I haven't seen any wiring diagrams specific to this. There has been mention of the 8 pin ISO connector possibly containing these outputs? If that were the case, do you think they would at line level or would I need an additional device to boost the signal? If you recall seeing anything similar to my situation, I appreciate you letting me know. Thanks again!
It's definitely possible. My PCCM+ is converting the signal through a line level converter from AudioControl, which converts the factory speaker wires (my system was non-Bose as well) to RCA, which then goes into an amp. This all works just fine.
What I don't know - is do you really even need a line level converter like one from AudioControl? There is a good chance it may not be necessary. Only reason I have it is because it was something the prior owner had installed - and at the time it was a more elaborate installation with a subwoofer (which I've removed) and multiple amps.
I currently have a large amp in the frunk that is powering the front speakers (component speakers). I just purchased a small amp I want to try to fit within the DVD area and clean things up and simplify. I'm going to first test this new/small amp through the AudioControl line converter to verify my sound isn't going backwards with the amp change. Assuming sound is good, the next thing I'll try is taking the AudioControl line level converter out of the mix and see how it works going straight into the amp - should be able to convert the speaker wires to RCA connections. I had to order a few misc. connectors to work through this but should be able to have one through all by hopefully this weekend can share what I learn.
isoConnector B, provides full 4 channel analog output - the connector wiring diagrams for the analog speaker outputs hasnt changed in 2 decades for all the german car radios that use that (standardized). That one is easy to dissect + create an RCA analog harness 4... there could be one out already since the schematic for 4 channel line out - isoConnectorB has been out for 20 years.
Originally Posted by maxw
It's definitely possible. My PCCM+ is converting the signal through a line level converter from AudioControl, which converts the factory speaker wires (my system was non-Bose as well) to RCA, which then goes into an amp. This all works just fine.
What I don't know - is do you really even need a line level converter like one from AudioControl? There is a good chance it may not be necessary. Only reason I have it is because it was something the prior owner had installed - and at the time it was a more elaborate installation with a subwoofer (which I've removed) and multiple amps.
I currently have a large amp in the frunk that is powering the front speakers (component speakers). I just purchased a small amp I want to try to fit within the DVD area and clean things up and simplify. I'm going to first test this new/small amp through the AudioControl line converter to verify my sound isn't going backwards with the amp change. Assuming sound is good, the next thing I'll try is taking the AudioControl line level converter out of the mix and see how it works going straight into the amp - should be able to convert the speaker wires to RCA connections. I had to order a few misc. connectors to work through this but should be able to have one through all by hopefully this weekend can share what I learn.
I'm struggling a bit as to where exactly the XM antenna should be mounted. The instructions on the box suggests putting it on the outside of the frunk by the windshield, or on the roof, but I'm not too thrilled with that option. I have a 997 Cab and was hoping I could get it to work by mounting it under the frunk lid in the area of the battery. Any suggestions and thank you for all the info supplied so far on this thread.
I fished my GPS antenna into the centre speaker location (I have an aftermarket amp so centre speakers are not supported) and the sat antenna can be easily placed under the cowl.
Im really sorry but Im not getting this diagram for the USB:
1. Is the +5v the upper left or right pin of the PCCM+'s 4-pin plug there?
with a VOM, it seems the upper left pin goes to ground so I dont want to short anything out.
2. Does that +5 feed back into the PCCM+ or only to the USB thumb drive, or to both?
Does anyone have a photo of a working modified 4-pin USB plug
isoConnector B, provides full 4 channel analog output - the connector wiring diagrams for the analog speaker outputs hasnt changed in 2 decades for all the german car radios that use that (standardized). That one is easy to dissect + create an RCA analog harness 4... there could be one out already since the schematic for 4 channel line out - isoConnectorB has been out for 20 years.
I've ordered an ISO connector and will try pinning RCA to wire ends into the B plug and determine the speaker layout. I'll try to do this on the bench with a power supply so I can test with an actual speaker. Thank you, this is promising!
I've ordered an ISO connector and will try pinning RCA to wire ends into the B plug and determine the speaker layout. I'll try to do this on the bench with a power supply so I can test with an actual speaker. Thank you, this is promising!
the diagram is online - you can't miss it. I have seen on the forums from another member that created this exact harness for his pcm 2.1.
Im surprised there isnt one out already as its been 20 years - and follows the basic german car standard across almost all german vehicles (if not more).
Im really sorry but Im not getting this diagram for the USB:
1. Is the +5v the upper left or right pin of the PCCM+'s 4-pin plug there?
with a VOM, it seems the upper left pin goes to ground so I dont want to short anything out.
2. Does that +5 feed back into the PCCM+ or only to the USB thumb drive, or to both?
Does anyone have a photo of a working modified 4-pin USB plug
+5v is taken from pin 4 off the white connector
look at the key on the connector in the diagram to know where to put it
What I don't know - is do you really even need a line level converter like one from AudioControl? There is a good chance it may not be necessary. Only reason I have it is because it was something the prior owner had installed - and at the time it was a more elaborate installation with a subwoofer (which I've removed) and multiple amps.
I'll try is taking the AudioControl line level converter out of the mix and see how it works going straight into the amp - should be able to convert the speaker wires to RCA connections.
Originally Posted by bxstrCA
I've ordered an ISO connector and will try pinning RCA to wire ends into the B plug and determine the speaker layout. I'll try to do this on the bench with a power supply so I can test with an actual speaker. Thank you, this is promising!
From this post - @maxw I believe the line level converter is a must. Note this 996 pccm+ post, they use a ISO adapter (with resistance) to reduce the gain (for an external amp connection). I believe those using isoConnectorB to extract analog outputs to a non oem amp, will indeed need to reduce the gain (with a line level converter or a harness adapter).
From this post - @maxw I believe the line level converter is a must. Note this 996 pccm+ post, they use a ISO adapter (with resistance) to reduce the gain (for an external amp connection). I believe those using isoConnectorB to extract analog outputs to a non oem amp, will indeed need to reduce the gain (with a line level converter or a harness adapter).
+5v is taken from pin 4 off the white connector
look at the key on the connector in the diagram to know where to put it
Thanks Stijn this is all helpful. I also found these hand-drawn diagrams posted here by another member back in January (sorry I cannot find the post again to give proper credit) that I think deserve a re-post as they helped me piece it together because they show the pins as they appear on the back of the PCCM+ and also a schematic from the 4-pin to the USB:
also happy to report that I got sound working (GT2 with Bose amp and subwoofer) the problem was that when the aftermarket system was installed by previous ownership, the installers disconnected a splice on one of the MOST fiber cables inside the dash. So, if you are factory MOST amp equipped and you find you have no sound, know that:
1 - the factory Bose amp does NOT need to be coded to the car with PIWIS / Durameteric; but
2- you must select "AMP" under system configuration, long-press "volume";
3- if still no sound, double check the fiber connections both ways by shining a light down one end and checking the other.
Also, you do NOT need to use the fiber loopback plug supplied with the PCCM+ kit. My car originally came with the amp, DVD based nav, and the old SXM box in the frunk, each daisy-chained to the fiber loop, so by removing the old SXM box (which by the way is NOT compatible with the PCCM+ (I tested)), and removing the DVD-nav, you would actually need two fiber loopback plugs. Instead, you can pop out the little blue piece in the middle of the unused fiber connectors, and then pop out the fiber, removing the two extra connectors, so you wind up with a simple fiber loop using just two terminations.
From this post - @maxw I believe the line level converter is a must. Note this 996 pccm+ post, they use a ISO adapter (with resistance) to reduce the gain (for an external amp connection). I believe those using isoConnectorB to extract analog outputs to a non oem amp, will indeed need to reduce the gain (with a line level converter or a harness adapter).
Thanks for info/reference here certainly good to know. I'll see if I can confirm is the case still on the new PCCM+ with some testing. I believe I have all the necessary wires up in the frunk so shouldn't be too difficult to try (hopefully).
03-06-2023, 04:16 PM
