Is my iDrive hosed?

[KnighTT]

Ok, so after 2 weeks of working on my new car after purchase, I finally get out and enjoy it on the road.

2008 135is with iDrive.

So, with enjoying a car, I go ahead and order what is needed to add Bluetooth streaming to the car so I can enjoy music while I enjoy said car. That is on the way. In the meantime I steal a aux cord and plug in my iPhone 7 to the aux port the old fashioned way.

No dice. Fiddle with the cord. Change the cord. USB does nothing either.

I cant select AUX on the iDrive.
Then I realize I can't select FM, or AM, or SAT.
All that works is the CD player with the single CD to my name because it came with the car. I can only listen to Lincoln Park so much.

Every once in a while the FM menu will just pop up randomly on the screen. Now it doesn't switch to FM radio, or interrupt the CD paying, it just randomly pops up.

So....

I'm guessing the iDrive system is having some issues. I rebooted the system a few times with the power/eject buttons but that solved nothing.

Before I give myself to the thought I may only have a CD player until I have to replace the CCC system, any advice on what may fix the issue?

[ultimated]

check your battery. It seems that when anything electrical is acting wonky in these cars, the first piece of advice is to check your battery.

[KnighTT]

FIXED

Turned out to be the TCU module.

I'm going to do a write up but you can bypass a bad module WITHOUT buying the loop connector.

There is a fiber optic connector block behind the driver side rear seat bolster. This block connects the lines together. What you do is disconnect all of the cables from the numbered side carefully with a precision screwdriver. #1 is the line directly from the CCC main unit up front. #5 is the end of the loop that goes BACK to the CCC unit to complete the loop. The rest of the connectors are the back and forth connections between the modules in the trunk.

I took out the radio and made sure I was actually getting a fiber signal from the radio in the first place then tracked the cable back to the block behind the bolster.

So, I realized I was getting a signal, visible, through to the block. I then plugged in the #1 connector and rebooted the CCC. Then I got a signal from the back of #2. This means the signal is successfully going through the first module and back to the block. So I plugged in the cable to the TCU in #2, but then nothing came back from #2 going to the #3 cable receiver. Well there you go. The TCU is not returning the signal.

So what you do is put #3 fiber INTO #2 slot. This bypasses the TCU and goes right to the next device. Then you will notice the #4 slot receiver start blinking. You have bypassed the TCU and the signal has gone through the next module. Then you plug in #4, then #5. This leaves the #3 slot open.

Now all of the functions of the radio are back. SAT does not work, who cares, and you have fixed the issue without having to buy a loop cable.

I now have my aux back, bluetooth, USB, radio, and CD. No issues. No money wasted.

I'm going to do another post with pictures and steps as I never came across a way to bypass a bad module for free. It is rather easy once you know the loop circuit.

[ianc]

Dude, you're fast on your way to becoming a guru. Nice work!

ianc