Nosubstitute531

I definitely do not have a multi disc cd changer since I don’t have anything in the frunk. But is the assumption that you have to get it coded if you don’t have a multidisc CD changer ?

What is this in the dashboard ? I’m able to insert 2 CDs in there.

qikqbn

Those 2 cd slots in the glove box are compact disc holders.. a place to store your favorite Kenny G cds

See post #466
I included the instructions page that describes dip switch positions. Since you do not have PCM head unit, you may want to try the "cdr" dip switch positions
Attached photo ... look under porsche dip switch setting for mr12volt

hehe

I’m throwing this out as an idea, not sure if this is true.
But could it be that in cars without Bose and Nav and Telephone and CD changer, MOST is not activated?
When the MOST loop is activated it recognizes which components are present and it’s basically plug-and-play.
You should be able to see if this is true, because the MOST cable coming from your PCM unit gives a red light when activated.
If there was no cable from the back of your PCM unit and no red light on the cable, my theory could be true and MOST is inactive.

Nosubstitute531

haha wow I had no idea that even existed.

My car does have PCM because when I pulled the deck out and looked underneath it said PCM 2.1. That being said I did play around with those switches based on what you had posted to no avail. The only thing I can think of now is that the car isn’t coded for the cd changer.

if someone can confirm that cars with no cd changers absolutely need to be coded I will give that a try at my dealer. Other than that I checked everything and it seems fine.

TEF

531, I share your problem with the LaPower, with two differences: My car has the Bose system and your phone does not see it as a BT device. In my case, the LaPower is BT visible on my phone, but like you I get the "No CD player" message. While the LaPower box has been in the car for more than a year, I've put off re-coding the car. Frankly, I have no Porsche dealer in my area and fear that re-coding might cost more than the LaPower.

Nosubstitute531

Wanted to post one last time to see if anyone else has any ideas before I conclude this unit is faulty. I have a PCM 2.1 unit. No cd changer, no phone, no navi and no Bose. I triple checked the voltage using a multimeter under the footwell connections and I’m getting constant 12 volts. I even got the cd changer option enabled using PIWIS. I’ve checked all the fiber optic MOST cable connections and they all seem to be connected perfectly (it doesn’t seem like there’s a wrong way to do this because the connections won’t fit).

all that being said - I still cannot get the mr12volt unit to work. Even after turning on the car I haven’t gotten any led lights to light up but I’ve heard that they sometimes don’t. My phone doesn’t find any Bluetooth even though I’ve checked all the connections.

Any ideas from the experts before I deem this unit broken and buy a new one ??

qikqbn

Sorry you are having issues. Unfortunately I am out of ideas. Can you post a picture of your head unit? The last resort would be to try and contact a Mr12volt representative. have you checked out the several youtube videos explaining installation?

lazyfatdog

Only suggestion I have is to post up your more specific location in the hopes that a fellow Rennlister with a working Mr12Volt might be willing to meet up and let you swap out the unit for a known working one. I was moments away from declaring my unit DOA when I decided to try installing the unit in my frunk instead of behind the PCM. Lo and behold, it worked. I have absolutely NO IDEA why it worked in the frunk but not behind the PCM, unless by some chance I had two bad FO loops (unlikely). My point is that these units can be tricking to get working for some of us, so throwing another part at it might just result in unnecessary expense.

Nosubstitute531

Alright guys I think I’m close but still need help. I bought a new mr12volt unit and installed and was able to connect my phone and get the led lights to turn on.




As mentioned earlier, I did program the car to enable the cd changer function using PIWIS. However, every time I press the CD button, I cannot get the PCM to recognize the mr12volt and as a result, no music to play or phone functions to work. When I press the button twice, all I get is no cd changer as listed below




To reiterate, my car is the base system: I have no cd changer, no Navi, no Bose, and no phone functions and PCM 2.1.

It just doesn’t make any sense why the pcm wouldn’t recognize the device even after I enabled it to have the cd changer. I’m very close to giving up and just living with what I have.

I reread the thread and noticed that there was another user who had the base system and wasn’t able to get it to work. I still don’t understand why if all the connections are correct and everything is coded properly but I can convince myself to lose this battle.

any help or advice will be appreciated

99-911

Hi
try connecting a media source (USB drive, SD card) then press CD.
for the phone since it's paired already, try making or receiving calls.

my 2cents..

hehe

Sorry, can't be of much help either.
I installed mine yesterday and it worked straight away.
I have no CD in the CD slot, when I press the CD button the screen says BT Audio.
I used the long end of the fiber optic wire for the Mr12Volt box and the short end for the PCM unit.

Only problem I have is an error message for missing phone module every time I start my car.
After I dismiss it the PCM and BT phone work fine.
Guess I will have to visit my dealer to get the phone module disabled with PIWIS.

8KaboveMSL

The MOST circuit has a flow direction, so switching up how the wires are connected could help. The first time I connected my MOST connectors up it didn’t work and I just changed up the which ends went into which connectors. There is a diagram in one of the previous posts. Suggest looking at that and seeing if changing up the connections helps. Just a guess though.

You’ve had some bad luck w/ a bad unit and now trying to figure out the PCM 2.1 “edge case.” I totally get your attitude. I have this saying that I’ve been repeating for years: I never take “no” as an answer from tech products. Stubborn to the end and have rarely had to settle for a “no” from a product. Rooting for you to figure it out!

RennKit-Dave

I believe you mean the fiber optic connectors, not wires. Also, fiber optic does not have a directional flow or "diode" effect. Light from either end passes through. You can hold a strong small flashlight up to an open end connector and see the white light on the other end. Switching ends has the same effect. It may come down to the connector and alignment of the FO pipes.

8KaboveMSL

thanks for technically accurate clarification.

my point is that there seems to be an expectation of the order that the devices are “seen” in. Not so much a layer 2 issue but perhaps a layer 3 and above issue. I am not familiar with this specific technology but a previous poster posted a graphic showing the order that devices are expected to adhere to. Almost implied the serial order mattered. Not sure if that is correct or not and that is what I suggested as something to try. Low cost effort frankly.

hehe

This is what I was referring to.
The fiber optic cable supplied with the Mr12Volt kit has a long and a short end.
If you use the long end for the Mr12Volt unit and the short end for the PCM unit the direction of the MOST signal is to the carkit first and from there to the PCM.
This seems to be the correct order