So this article is about quite standard problem you can find on lots of cars, but here its about BMW. So you started getting first random lights on the dash and later it became permanent lights on mess on the dash. Usually you get ABS, DSC, DTC, BRAKE lights on and some messages on the idrive, like drive train malfunction, etc.
Lots of mechanics diagnose it as bad abs sensors, abs pump etc, because it shows these errors on the scanner.
YES, IT WILL NOT TELL YOU THAT ABS MODULE IS BAD, IT WILL ONLY TELL YOU WHAT SIGNALS ARE LOST, THEREFORE YOU END UP REPLACING LOTS OF WHEEL SENSORS, ABS PUMPS, SWITCHES AND SO ON. THE ANSWER IS INSIDE THE ABS UNIT-TINY GOLDEN WIRES BROKE OFF FROM AGE AND VIBRATION AND THAT’S WHY YOU GET ALL THOSE ERRORS!
SO SIMPLY REPLACE ABS/DSC UNIT WITH A NEW ONE (600$+)OR GET IT REBUILD FOR 100-150$ WITH WARRANTY. NOTICE NEW CLEAN MODULE DOES NOT NEED CODING- IT IS SELF CODED, SIMPLY IT WILL WRITE VIN NUMBER AFTER YOU CONNECT IT FOR THE FIRST TIME, SO DON’T PAY ANYONE FOR “CODING” NEW UNIT. USED UNIT NEEDS TO BE REPROGRAMMED, BUT I RECOMMEND NEW UNIT OR REBUILD YOURS.
This amplifier is different than E65 Logic7 amplifier, it runs different software and cannot be installed on either. This amplifier has 9 channels vs E65 with only 5 channels. This amplifier controls all the speakers on the car, so if it goes bad you will not hear any sound in any speaker. But not always amplifier is the problem, in some cases other modules go bad, interrupting MOST network and you will not hear any sound even with working amplifier. So here i will explain how to diagnose if it is the amplifier or something else went wrong.
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
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: It 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 1200$.
HOW TO BYPASS NON WORKING MODULE??? EASY! GET THIS P/N FROM ANY BMW DEALER 61136917541, YOU CAN GET IT ONLINE FROM ECS TUNNING ECS TUNNING FIBRE OPTIC JUMPER. YOU HAVE TO REMOVE INNER PART WITH SOME FLAT SCREWDRIVER OR A KNIFE, YOU CAN ALSO USE ZIP TIE IF YOU PLAN TO
IF YOU DECIDED YOU NEED HELP WITH AMP REPAIR 550$ PAYPAL PAYED TO LOGIC7REPAIR@GMAIL.COM.
We have also EBAY add, so you can see real feedback.CLICK THE PAYMENT LINK ON THE TOP OF THIS PAGE, MAKE A 550$ PAYMENT, PRINT A RECEIPT AND INCLUDE IT IN THE BOX WITH YOUR AMPLIFIER OR ASK UNIT AND SEND IT TO OUR ADDRESS (SEE BELOW). USUALLY IT TAKES 1-2 DAYS TO REBUILD IT AND 2-3 DAYS SHIPPING. INEXPENSIVE AND FASTEST SHIPPING IS USPS PRIORITY MEDIUM BOX (12$).
THIS AMP IS QUITE COMPLEX INSIDE AND YOU CAN SEE NOT MANY OFFER THIS REPAIR, SOME OFFER IT AT 500$++ FOR A REASON, IN SOME CASES LIKE BAD WATER DAMAGE OR SUCH ITS NOT EVEN FIXABLE.
In this post we will be describing how to diagnose MOST bus failure in any BMW, AUDI, PORSCHE, ROLLS ROYCE, RANGE ROVER HSE, BENTLEY with MOST fiber optic bus. every car has different configuration, but principle is still the same!
So in 2000 they introduced newer multimedia bus, called MOST, IT IS VERY NICE AND FAST NETWORK, SO THERE IS ENOUGH SPEED TO CONTROL EVERY MULTIMEDIA DEVICE AND THEY ELIMINATED LOTS OF COPPER WIRES IN THE CAR. NOW SOUND IS FULLY DIGITAL AND CLEANEST (BC NO SIGNAL LOSS ON THE WIRES), SO IT IS A GOOD THING, BUT ITS MORE COMPLEX AND NOT VERY RELIABLE.
So to start you need to understand that all MOST (multimedia) modules in the car work in the closed loop, which means if any device in the loop fails-none will be working.MOST bus primary signal (optical red light signal) is generated inside of the main computer, which is your main screen CID (control display or CID in E65 car only, other BMW have main computer incorporated into head unit or CCC/CIC/NBT etc), then it travels through all MOST network devices (ask unit, amp, navi, fm tuner, phone etc. depending on how many options you have) and comes back into main head unit. Basically all units connected in the loop- one unit fails=broken network! Once you understand this principle, you can easily find broken unit or network interruption, don’t forget dealer will charge up to 500-1000$++ for such a serious job! You don’t believe me? go and try, then you will understand how priceless with post is.
Your E65 E66 or Rolls Royce phantom ( yes don’t be surprised it is the same exact car as your 760li btw) car has MOST bus failure if:
-cannot hear any sounds or music
-cannot see tracks playing on the display
-fm stations not available
-navi isn’t functioning
For other BMW like e60/e90/e70/e89/f01 and others MOST BUS FAILURE symptoms are little different because primary head unit has 4-5 modules (SVS, ask unit, MOST GATEWAY, NAVI, Radio tuner) combined and therefore everything will work except for those secondary modules: -amplifier no sound and you see mute icon on the radio or screen -TCUM or telephone module -SAT NAV receiver
Here is the MOST DEVICES order diagram , but this is only valid for basic order and only for pre 2006 cars, you might have way more devices in the network, so you have to figure it out yourself by looping eac modules and draw a diagram of the modules.
Here is a quick video showing how to find a bad unit in real time:
FOR 2006-2008 E65 E66 cars basic order will look like this:
MMIGT(screen)>>CDC>>AVT(if you have it)>>TEL>>SAT(hd RADIO)>>L7>>SVS>>NAVI>>ASK>>OOPS(GLOVE BOX MOST LOOP)>>MMIGT
FOR E60 E90 E63 E89 E90 E92 E93 and so on:
HEAD UNIT CCC/CIC/NBT>>L7AMP>>SAT>>TCU>>MULF>>HEAD UNIT
On these cars in most cases i see sat and amplifier unit failure very often, telephone module goes bad too but not that often.CCC navi units have a high rate failure, but the good thing once you replace it, you replace 5 modules at once, so its more reliable and much easier to find a faulty unit because you only have 2 or 3 modules to diagnose and all of them located in the trunk. We also offer CCC or CIC repair service
So to find out the faulty unit you either need to see a dealer (but even dealer makes mistakes), but here is an easy solution if you don’t have anything, and if you do it right it always works:
You need basically to find out where the most signal gets lost, after what device you don’t see the red light. In other words you will be checking the red light after every device in the network, and the one which is not sending the red light signal is your FAULTY MOST UNIT. OOPS is the last diagnostic connection located in the glove box and it has lollipop attached and it has to be looped there, some people think it is a spare jumper, but its not, without this jumper you will interrupt the network!
HOW TO BYPASS NON WORKING MODULE??? EASY! GET THIS P/N FROM ANY BMW DEALER 61136917541, YOU CAN GET IT ONLINE FROM ECS TUNNING ECS TUNNING FIBRE OPTIC JUMPER. YOU HAVE TO REMOVE INNER PART WITH SOME FLAT SCREWDRIVER OR A KNIFE, YOU CAN ALSO USE ZIP TIE IF YOU PLAN TO KEEP THE JUMPER BYPASSED, IRT WON’T STAY WITHOUT ZIP TIE.
most common MOST devices failure (descending from most common to less):
-SAT SIRIUS unit always goes bad, we will offer repair of this unit soon
–TCU TELEPHONE BLUETOOTH MODULE RECENTLY WE SEE TONS OF THEM FAILING!
-Logic7 amp AMP
-ask cd unit ASK
-navigation NAVI
-fm tuner
-CD itself main screen CID
-cd changer CDC
-SVS (gets flooded with hydraulic fluid from trunk opener cylinder, if you see sticky fluid on the NAVI, SVS- replace asap)
other modules. depending what you have in your car
Always check if you have red light in the glove box, disconnect that jumper and check for the light, if you found and bypassed bad unit correctly you should see the red light in the glovebox and then you can install the jumper and everything should start working. I know it sound complicated but once you understood how it works it is kind of very easy.
BUT PLEASE DO NOT BLINDLY BYPASS EVERY MODULE, LIKE LOTS OF PEOPLE DO, YOU MIGHT FIND THE PROBLEM, BUT ITS NOT EFFICIENT AND SOMETIMES YOU CANNOT DIAGNOSE IT RIGHT. ALSO MAKE SURE EVERY MODULE HAS 12v POWER. BASICALLY EVERY MODULE NEEDS FIBER OPTIC SIGNAL AND 12V POWER ATTACHED TO FUNCTION.TO WAKE UP MOST NETWORK IT IS ENOUGH TO OPEN/CLOSE THE DOOR, YOU DON’T HAVE TO START THE CAR, THE THING IS MOST GATEWAY WILL GO TO SLEEP AFTER 10 MINUTES IF NETWORK IS BROKEN AND TO WAKE IT UP YOU NEED TO OPEN/CLOSE ANY DOOR OR TURN ON THE RADIO.
THAT’S about it, IF YOU FOUND THE BAD MODULE YOU JUST SAVED 300-400$ AND TIME. REMEMBER LOTS BMW SHOPS STILL CANNOT DIAGNOSE IT RIGHT AND ALWAYS POINT TO ASK UNIT OR AMPLIFIER, “BECAUSE THERE IS NO SOUND”, WHICH IS NOT ALWAYS TRUE, I WOULD SAY IN 50% ITS NOT CORRECT EVEN FROM OFFICIAL DEALERS. WHY THEY MADE IT SO COMPLICATED AND NOT RELIABLE?? WELL THIS A FUTURE OF CARS AND TECHNOLOGY, YOU ARE THE ONE WHO ASKED TO HAVE ALL THESE TOYS IN THE CAR, SO YOU EITHER LEARN IT OR HAVE YOUR WALLET READY TO GET SKINNIER, OR BUY HONDA/TOYOTA….
Disclaimer: By sending us the unit for repair you do authorize us to work on your unit. Please make sure your shipping address is correct: unit can only be shipped to the address you specified during payment, no exceptions! $100-$150 diagnostic fee will be applied if the unit needs no repairs. If you bought a replacement unit from us and your original unit was misdiagnosed as faulty we can only offer 50% refund. This is due to time spent on coding and preparing your unit plus shipping cost. Dismiss
