[NicoSuave]

Hey guy, I have a 2006 330i with HIFI LOGIC 7 and I haven’t had sound in my car for some while now.. and I can not do it anymore. I can’t even begin to explain how many hours I have invested into trying to diagnose this problem.

First thing I did was take my Autel Maxicheck and ran a diagnosis. Amp is good, and radio is good - accord to the scan.

I am getting a TCU (short circuit to positive) code.
I’ve looked up the MOST diagnosis, and did all my fiber optic tracing.

Went to the junkyard and grabbed the fiber termination plug, that is under the dash, unplugged it from the TCU and put the female connecter on.

I am now getting the red blinking light at the plug under the dash but still no sound.

Fiber plug at the amp has blinking light, and amp has steady yellow light.

When I unplug the harness from the back of the radio, I have no red light from the fiber plug part of it.. but I’m wondering if the radio is what emits the light?

I’m at a loss and really can’t afford to replace things on a whim. Need to be a for sure thing.

Is the female plug under the dash the same exact thing as a fiber optic loop? My guess is it was, but if that is the case; why do the aftermarket plugs have a large loop of fiber? Wondering if my best bet is to order a real fiber loop for the plug in the trunk?

When I took the amp out and half apart, it was filthy.. I cleaned it up and put the top back on. I kind of want to rule the amp out because of the solid yellow light?

I also heard a theory (which I find hard to comprehend) that the front speakers should be playing if the amp was out bc...?

Any help is much appreciated (sorry for the scattered post, writing from my phone)

[ctuna]

Makie sure you know which system you have Logic 7
is option 676 in 06's

BMW stereo types
http://www.e90post.com/forums/showthread.php?t=352586
http://www.e90post.com/forums/attach...2&d=1266451970
http://www.e90post.com/forums/attach...2&d=1260829447
http://www.e90post.com/forums/showthread.php?t=343673
http://www.e90post.com/forums/showthread.php?t=138949
http://www.e90post.com/forums/attach...1&d=1209780605
http://www.e90post.com/forums/attach...1&d=1209780865
http://www.e90post.com/forums/showthread.php?t=641323
http://bmwcoders.com/forum/3-er-8/bm...1-e92-e93-291/
http://technicpnp.com/menuDiagrams/d...e90_92_93.html
http://www.musicarnw.com/page-2/
http://www.e90post.com/forums/attach...3&d=1169133185
http://www.e90post.com/forums/attach...4&d=1278871872

Logic 7
https://www.e90post.com/forums/showthread.php?t=1056432
http://www.bmwlogicseven.com/?p=3837
http://www.bmwgm5.com/
https://www.e90post.com/forums/showt...5#post24455335
http://www.e90post.com/forums/attach...2&d=1260829447
http://www.google.fr/url?sa=t&rct=j&...slMu2A&cad=rjt
https://www.bmwgm5.com/Logic7_E90_91_92_93.htm
http://www.bimmerfest.com/forums/sho...d.php?t=982666

http://www.e90post.com/forums/attach...1&d=1209780605
Most
http://www.e90post.com/forums/showthread.php?t=727663
http://www.e90post.com/forums/showthread.php?t=347222
https://www.google.com/search?q=BMW+...VCkMqy2aCK09M:
http://www.1addicts.com/forums/showt...php?p=19256760
https://www.teacremotes.com/bmwgm5/
https://www.e90post.com/forums/showthread.php?t=347222

There are LED's on the amp that tell you some things about what is
happening .
See second link under Logic 7 header.
All the speakers are powered by the Logic 7 amp.
in a 06 330's
Is this car new to you? Do you know the history of replacement of
any of the audio parts? Do you have any other modules on the Most
Bus like a sat module?

Tcu short circuit does this mean its blowing fuses or just showing up
bad on whatever scanner you are using.
By the way I would not try updating your car with any non BMW
scanner.

[NicoSuave]

I have the HIFI with option #S677A I’ve had the car for around two years. All the audio is stock. I haven’t done any updates from the scanner. And the light reading it is having , should be connected to a working amp. Solid yellow.

[ctuna]

There is more than one LED in the amp.
Did you read the article on reading he LED's

This amplifier has a diagnostic LED, which will show lots of things you most likely don't know about. Here you can see where it is located. So look at that LED, turn on the radio and look at it:
basically: blinking yellow -check or bypass sat tuner or Bluetooth tel module no yellow- amp is bad steady yellow but no sound or bad sound- amp is bad e60L7led

Steady yellow means its getting input fiber optic signal from the head unit (CCC or CIC) and output signal travels to the head unit correctly through other units , so you should hear the sound in most cases, but rarely it also could be some software glitch with CCC, when you don't get sound with working amp. Try CCC reset.
Blinking yellow means AMPLIFIER IS WORKING and getting input signal from the head unit, but output signal is somewhere lost due to the next bad unit in the loop. So you just need to find a bad unit and either bypass it or replace it with a working one. Most common units to fail are: Sirius satellite unit, Bluetooth telephone unit

No Yellow LED, but you can see blinknig red LED deep inside most likely means 3 things:
amp is bad
no power getting to the amp check last 2 thick wires red and brown 12V should be present always, otherwise check fuses in the trunk.
No fiber optic input getting into the amp from head unit, but in this case you should see a red LED on for 15-20secs, this means amp is waiting for a signal and if no signal present it will go to sleep mode. Easy to check, you should see a blinking red LED in the CAR CONNECTOR with the amp fiber optic connector disconnected. If its blinking it means head unit is sending signal to the amp and amp CPU has to accept it and send the output signal back to other units and head unit eventually. Rarely, But if no red led present in the connector it means no signal is coming from the head unit due to either bad head unit or some fiber optic wire damage. If you remove head unit and you see a red light blinking, you should see the same blinking at the amp connector.

So basically you should get steady yellow LED at the amp, which will indicate the network is working, bypass not working modules and if amp is good you will get sound back to your car!
These amps are much better design compared to E65 design, but they still go bad due to following reasons:

Water damage especially on convertibles 6 series, almost always we see this problem: E64LEAKIt happens when water drainage pipes get clogged up with dirt and thanks to smart design all water leaks onto the amp and other units. Please always clean those pipes with compressed air and some soap. On 3 series we see rear taillight bolts getting loose and therefore it leaks water inside.
Actual CPU failure or other things go bad inside the amp. We can help in this case, but can not guarantee 100% success, usually we see 60-70% success rate vs 90% e65. Good thing these amps are quite cheap on Ebay or junk yards, or new from the dealer

The above from

http://www.bmwlogicseven.com/?p=3837
where there are pictures.
Also these guys do repairs.

option 677 is called top hi fi or more commonly L7

That would indicate a bad amp .
No diagnostic can check the output of an amp .
Sound coming from it is the only test for that .

[NicoSuave]

I’m not blowing any fuses, that I can find anyways.

Is the plug under the dash the same thing as a fiber loop? When I unplugged the TCU and put the jumper on the plug, I got the red light under the dash. But still getting an SOS.

So if I tried all the above.. and getting a steady yellow amp light - sounds like the amp?
I have tried to unplug the battery for an hour to reset CCC, still nothing.

Sounding it is the amp :/

[ctuna]

The plug under the dash is a Most Test Point for BMW shop's
Its just a point where they can plug test equipment into the loop.
You will break the loop if you leave it unplugged.

You can buy most jumpers very cheaply on amazon.
Another trick to check fiber is to shine a light down one
end and see it come out the other.

It's not surprising that if you unplug the device that generates the SOS
it gives and error.
You can program that unit out of the Car if it's bad and you don't want to use
it anymore but bluetooth phone an voice controls also come from there.
It can be replaced with more useful devices like a Mulf 2 Hi
which gives bluetooth phone calls and USB or easier is this.

http://www.e90post.com/forums/showth...4#post23244354
sd card usb card, streaming bluetooth phone and music another aux
requires enabling the cdc function.
Steering wheel controls but no voice function.

Both require programming
The Mulf 2 Hi is trickier programming.

TCU = voice control , sos function no longer supported by bmw in US
bluetooth phone.
Mulf 2 Hi Blue tooth phone voice function and USB.

[NicoSuave]

Ok, so you say I will break the loop if left unplugged, so the female part of that is a loop?
Because I went to a junkyard. Grabbed another female plug from that test point, and put it on the plug back where unit is in the trunk. Would that not serve as a loop?

[ctuna]

The loop/jumper is just a piece of fiber to point one end at another.
I would guess that plug is the same as the jumpers you buy anywhere
else .
You could probably use a straw to point one end at another.
Buy taking out the clip that hold the fiber in place in
the connector .
You can also re route stuff at the most hub.
There was a good picture of the entire loop in that first video.

Don't know why you are messing with that jumper if you are seeing
a solid yellow light in the at the amp led it's indicating there is nothing wrong with the most bus signal between he amp and head unit in either
direction.

[NicoSuave]

I am messing with the connector because prior to me getting the plug from the yard, I was not getting a red blinking light at the plug under the dash. All this was stated in my original post. So now I am getting a light under the dash, a solid yellow light on the amp, and no sound.

[NicoSuave]

Also, is the radio harness supposed to have a blinking light when unplugged or no?

[ctuna]

Since you where bypassing your TCU as part of the process
and it didn't help maybe your tcu is OK . You could try plugging
the TCU back in and moving the jumper to the amp , then if the
SOS error goes away you would at least know its not your TCU.

You don't have a Sat module do you ?

You would have to try your amp in a working car to do a verification
that its good if you want to be absolutely sure.

[NicoSuave]

I thought the same thing about the TCU, so I plugged it back in. After plugging it back in, I was no longer getting a red light at the plug under the dash.

I was going to put the jumper on the amp, but the connection is somehow different than all the other plugs.

[ctuna]

That kind of verifys the tcu is bad as long as it has power.
It's unusual for more than one module to have a problem
but it can happen.

Was the audio working on this car when you got it?

[NicoSuave]

Yes it was. It just went out recently. It did start intermittently, some days I would get in the car and it worked.. other days it didn’t. Until one day it just didn’t come on anymore.

I wish I had an amp or car I could plug mine into. I asked the guys at the junkyard and quickly got shot down lol

[NicoSuave]

This is what I was talking about. Does that sound right to you ?

[ctuna]

That's for 2003 to 2007 6 and 7 series they stopped doing that
distributed system a long time ago. Man I gave you those official documents
I guess you don't believe in reading.


http://www.e90post.com/forums/attach...2&d=1266451970

[NicoSuave]

Haha my bad. I’ve gone back and forth between so many articles - it’s hard to keep it all separate in my head! Took a voltmeter to the amp tonight. Think I found some things to raise an eyebrow to.

[ctuna]

https://www.e90post.com/forums/showthread.php?t=1144129

[NicoSuave]

Saw that article before.. do you have any sources that diagram the board? I have some sound experience - but breaking down the amp to the board is new for me.

[Black_Valkyrie]

to clarify, have you actually put your hands on the amp in the trunk? By any chance is it submerged in water or was it? If so a complete dismantle and dry out will solve it.

[NicoSuave]

Yes sir, I have it here sitting in front of me in the living room. Don’t think water was ever an issue. Although I do see some marks where something shorted out on the side of the amp. I am making a video, and will post back soon

[ctuna]

Nothing beyond that it's the only time I have seen anybody take it apart.
The guy that tells you how to troubleshoot with the led's repairs them.
You are kind of stuck in that loop where you don't know what's good and
bad until you verify the amp some way.

I used to repair mini computers and semiconductor test equipment for a living . I would sometimes replace output transistors on stereo receivers. Sometimes you can get the part number and tell what things are suppose to be doing in analog sections of electronics but in the digital portion if it involves processors and custom chips you are pretty much out of luck.