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VCDS is a useful tool, it can point you in the right direction, I wouldn't discount it. Still, you definitely need to combine it with traditional diagnostic techniques. Understanding how the system works goes a very long way.
As 'Jack88' says, VCDS is not a 'solution provider' but it IS almost vital for getting clues.
From what I can see from the Autoscan, in conjunction with the optical scan, it's starting to look like a Control Head problem:
: ALL of the optical bus ECUs are 'down' according to the optical scan - I believe the optical master signal is generated by the control head
: You can't reach the Control head in the scan
The optical scan runs; but this is run as a test by the Gateway ECU, so the fact you can run it indicates the Gateway is OK. [But note that both the Control Head and the Amp's electrical connections have failed].
But the Control Head may not be the only problem; I'm not sure if the MMI ECUs can be reached if the optical bus is down.
You've also got some faults with older dates [Address 4F].
You've also got battery manager shutdown issues too [Address 61].
For some strange reason you've cut the date and time header off the top of the scan, so it's not imnmediately obvious what the date and time relationship is between the fault logs and the time you ran the scan.
Julian
Last edited by JulianHicks; 08-02-2018 at 05:12 AM.
Yeah I came to that conclusion and have been looking at Control head modules, but too busy to buy one yet. There is a youtube video on replacing, done by the co that refurbs the boards. They are making a small career out of fixing these puppies.
What is the best way for replacement?? Get a refurb or toss in something with USA Nav and get the component protection lifted by the dealer or ??
The date got cut off cause my laptop touch pad is pissy to work with. The scan was done at this time:
Date: 2018.07.30
Time: 10:47:41
What is the best way for replacement?? Get a refurb or toss in something with USA Nav and get the component protection lifted by the dealer or ??
The 'official' view is that Control Heads are protected by CP, but others on this forum have claimed to have fitted replacement CH's that haven't gone into CP. I haven't changed mine but I'd assume that a different CH WILL go CP if you fit one. [Note - the USA navigation is only indirectly related to the CH as navigation runs in the seperate NavBox in the boot [trunk]. The USA CH's do run a US version of the MMI though].
There would appear to be two/three options:
1) Get your own CH refurbished - No CP.
2) Get an 'auction site' CH but make sure it's compatible. You might get an A6 or Q7 one to work but I'd get an A8 one off a US site. CP likely.
3) To avoid CP; get auction site CH and move your chip to the replacement CH. Not an easy option in my view. - No CP.
Julian
Last edited by JulianHicks; 08-04-2018 at 12:22 AM.
Reason: Typos
Hi - thanks for your input. I pulled the glove box today and got at the module. I mean you could fry an egg on the thing** and it smelled burnt. That sucker was drawing current big time, which explains why it was nuking my battery, to the point of dead flat this past week.
Ordered a new module off Ebay for $70, just now. We'll see how that goes....
Ordered a new module off Ebay for $70, just now. We'll see how that goes....
That looks a good price - is it an A8 Control Head?
As it comes from a different car, don't forget you need to prepare for:
: Updating the Coding
: Updating the Adaptations
: A possible updating of the MMI level
Yea, you need to make sure it’s for an A8, specifically the sw version part number begins with 4E0. Non A8 ones won’t work properly and you won’t be able to remove CP. They also will not recognize the MMI screen open/close function.
Also, try and get one with the green FBAS connector as that will then give you video in capability for reverse cam, TV tuner and the associated A/V inputs.
Also, try and get one with the green FBAS connector as that will then give you video in capability for reverse cam, TV tuner and the associated A/V inputs.
HW [hardware] part numbers are:
4E0 035 729 - Without green FBAS video connector - label shows "Model No: BE 6346" on A8 model with US MMI
4E0 035 729 A - With green FBAS video connector - label shows "Model No: BE 6348" on A8 model with US MMI
Julian
Last edited by JulianHicks; 08-08-2018 at 11:19 AM.
Reason: Enhance label descriptions
HW [hardware] part numbers are:
4E0 035 729 - Without green FBAS video connector - label marked BE 6346 in US model
4E0 035 729 A - With green FBAS video connector - label marked BE 6348 in US model
Julian
As mentioned, the SW [software] number is also critical. The 4E0 035 729 HW number is generally the same one as used in the A4, A6, Q7, etc. However they all have model specific SW numbers. Anything with a SW number not beginning with 4E0 won’t work correctly in an A8. You need to be able to clearly read the sticker on the module in the ad to confirm as this important detail is rarely included in the item descriptions.
Well if that’s the actual unit then the SW is the A6 version as it starts with 4F0 which is the C6 A6 model code. Screen shot below.
You might get lucky, but installing that will very likely give you unresolvable CP problems, as well as other glitches. Running the MMI update won’t make any difference unfortunately as this is something that’s apparently hard coded.
08-02-2018, 05:09 AM
