VAG-COM
Audi Issues &
Problems
Concert
and Symphony Radios
These are made by
Matsushita. Some of them appear to have bugs in the diagnostic
protocols. I have already added one work-around to the low
level protocol drivers that works in some, but not all
Concerts. Some Symphonies work perfectly (like the one I
purchased so I could pursue this issue). Other Symphonies are do not
communicate reliably. I would like to get my hands on
"flaky" Symphony Radio so I can investigate further.
Some Concerts occasionally get "stuck" in an undesirable mode after attempting communications. If your Concert get's "stuck", the way to reset it is to remove all power from from the radio for at least 10-15 seconds. This can be done by:
-
Removing the radio from the car.
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Disconnecting the car's battery
-
Pulling the fuse for the radio.
Note: Some radios will require you to enter the "security code" using the radio's front panel after loosing power. See the your owner's manual for the radio for instructions.
1994-1997
C4 (A6/S6) Instrument Clusters
These have a
high bit-error rate. I suspect they use a software-UART and
"stretch" bits sometimes. The error-detection/correction
logic built into VAG-COM's low-level protocol drivers as of version 0.70
seems to take car of this in a majority of cases, but I still
had few reports of customers not being able to communicate with these
clusters. In version 0.75 or or newer, please
ensure that Char Int on the Options
Screen is set to approximately 3 (which is the default).
On some PC's, it may be necessary to adjust this value to something other
than 3. On very fast PC's try a higher value. On very slow
PC's, try something less.
1992-1994
2.6L V6 Engine (non-US only)
VAG-COM cannot
communicate with some of these ECU's. I do not yet know what
the problem is. The DEBUG files don't tell me enough. It looks
like some sort of protocols timing issue, and that means I have to get an
ECU to play with. Unfortunately, they are hard to find in the
US since we never got the 2.6L V6 here.
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