MOST (optical comms) issue

[Dippy]

Shortly after getting my S5 I saw some DTCs in a scan which cleared and could have been due to the work I had been doing with VCDS so didn't think much about them. They haven't re-appeared for many scans but did again yesterday. They are:

19 CAN gateway
00384 - Optical Databus
011 - Open Circuit - Intermittent

5F Information Electr.
02067 - Optical Databus; Unpermitted Wake-Up Request
000 - - - Intermittent

These seem to be fairly common and possibly related to retrofits, but that's not my case - my car is 15 weeks old from new. Obviously its under warranty so I'll get it checked out at a dealer sometime but there are no obvious symptoms - everything seems to be working fine - so I'm not in a hurry, I'll wait for the next service.

Nevertheless I'm interested to see if I can find out any more about this hence this post to see if anyone else has had such issues.

I did the VCDS optical bus diagnostic and it returned 'OK' for 19 (CAN gateway), 47 (sound system) and 56 (radio). This surprised me because I'm sure there should be other equipment on the bus. I decided to try again with the 3dB attenuation option but it failed, with 'ERROR' for 56. I then had other DTCs:

19 CAN gateway
00384 - Optical Databus
011 - Open Circuit - Intermittent

47 sound system
03278 - Functionality Limited due to Missing Messages
000 - - - Intermittent

56 radio
03278 - Functionality Limited due to Missing Messages
000 - - - Intermittent

5F Information Electr.
03157 - Functionality limited due to Communications Disruption
000 - - - Intermittent
03278 - Functionality Limited due to Missing Messages
000 - - - Intermittent

Again these all cleared and I did a final autoscan which had no errors.

I assume that I must have a bad optic connection somewhere. Can anyone share any similar experiences?

 

[Chitimiea cosmin]

Hello,i have exactly the same probleme,please help me,what can i do???I have an facelift audi A5 2014

 

[Aplatt22]

Hey there, did you ever get this issue solved? If so, what was the fix? I have a 2014 q5 with the same 00384 and 02067 codes being thrown now at 74k miles. Just had it in at the dealer too for a DEF wiring harness replacement and am now wondering if it is somehow related to these new codes. These codes also came on basically right when my lane change assist threw a code, C1115F0, which I think is related to the slave module in the rear bumper as the sensors all still work. Any help with any code is greatly appreciated!

Shortly after getting my S5 I saw some DTCs in a scan which cleared and could have been due to the work I had been doing with VCDS so didn't think much about them. They haven't re-appeared for many scans but did again yesterday. They are:

19 CAN gateway
00384 - Optical Databus
011 - Open Circuit - Intermittent

5F Information Electr.
02067 - Optical Databus; Unpermitted Wake-Up Request
000 - - - Intermittent

These seem to be fairly common and possibly related to retrofits, but that's not my case - my car is 15 weeks old from new. Obviously its under warranty so I'll get it checked out at a dealer sometime but there are no obvious symptoms - everything seems to be working fine - so I'm not in a hurry, I'll wait for the next service.

Nevertheless I'm interested to see if I can find out any more about this hence this post to see if anyone else has had such issues.

I did the VCDS optical bus diagnostic and it returned 'OK' for 19 (CAN gateway), 47 (sound system) and 56 (radio). This surprised me because I'm sure there should be other equipment on the bus. I decided to try again with the 3dB attenuation option but it failed, with 'ERROR' for 56. I then had other DTCs:

19 CAN gateway
00384 - Optical Databus
011 - Open Circuit - Intermittent

47 sound system
03278 - Functionality Limited due to Missing Messages
000 - - - Intermittent

56 radio
03278 - Functionality Limited due to Missing Messages
000 - - - Intermittent

5F Information Electr.
03157 - Functionality limited due to Communications Disruption
000 - - - Intermittent
03278 - Functionality Limited due to Missing Messages
000 - - - Intermittent

Again these all cleared and I did a final autoscan which had no errors.

I assume that I must have a bad optic connection somewhere. Can anyone share any similar experiences?

 

[***DK***]

I could be wrong but I thought most of the time the MOST optical bus issues are linked to the optical wire that travels from the trunk radio units to the front MMI head unit and then onto other parts, possibly Bluetooth module etc. Might be worth checking units in the boot compartments and that the optical wire is properly seated then working to the other units. People also buy the optical diverter loop tool to work out which device is having issues (the error going away when you divert the MOST around the failing unit). Sometimes water damage causes MOST errors.

Sent from my NE2213 using Tapatalk

 

[Dippy]

Hey there, did you ever get this issue solved? If so, what was the fix? I have a 2014 q5 with the same 00384 and 02067 codes being thrown now at 74k miles. Just had it in at the dealer too for a DEF wiring harness replacement and am now wondering if it is somehow related to these new codes. These codes also came on basically right when my lane change assist threw a code, C1115F0, which I think is related to the slave module in the rear bumper as the sensors all still work. Any help with any code is greatly appreciated!

The only "issue" was that I saw the entries in the log. There were never any symptoms and I never saw them again.
Do you just have the codes or are there other symptoms of a problem?