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Why is SDS showing "f" against control units, but I can't find any fault codes?

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1.5K views 18 replies 4 participants last post by  M4rCu5  
#1 ·
For background, I'm chasing an intermittent fault whereby when I transverse a particularly rough road (potholes especially) my roof switch starts flashing and the beeper beeps. Beeper stops for some time then repeats for some seconds. Switch flashes all the time. Stopping the car and raising the roof resets both - yes, it closes electrically.

Anyway, the purpose of this thread: When I connect SDS and read the fault codes I always see a small "f" against the CCM and VR. I take note of the codes and reset them all. They all always reset successfully (so SDS tells me). I understand a small "f" to mean the code is historical and the fault is no longer there.

But when I repeat "quick test" I still get "f" against the CCM and VR. Interrogating the control units again shows no fault. How can this be? How do I get quick test to show ticks against all control units? Or, alternatively, how do I see what's causing the "f"s.

There is a permanent fault code on the VR: B1493 Gong control wire. Others have this and it appears it's caused by the smarttop installation. However, as SDS shows no codes after resetting them all, can I assume it's not there until I operate the roof?

I used to have a full house of ticks on quick test. Can anyone help me identify these annoying "f"s?
 
#2 ·
@M4rCu5 and I had a serious battle with same situation, but different components!
The CCM has signal from....devise and blocks the roof.
If the CCM has all signals "normal" the roof operates if only 1 condition is met - speed limit!
Under (I have no idea if you have smart top) factory set parameter. Saying 10km just as example here!
So I think you need to chase the "signal" from CCM. Take a look at the fault and see if the SDS will suggest a thing, before that - charge your battery!
Yesterday we saw a Christmas Tree for plenty of errors here: https://www.slkworld.com/threads/car-wont-turn-off.600685/post-4959897
And about 50 min to clean them up (timestamp on the bottom of documents).
Keep in mind one more factor - SDS isn't always as we want it to be.
 
#12 · (Edited)
BaD_81 said:
Yesterday we saw a Christmas Tree for plenty of errors here: https://www.slkworld.com/threads/car-wont-turn-off.600685/post-4959897
And about 50 min to clean them up (timestamp on the bottom of documents).
Keep in mind one more factor - SDS isn't always as we want it to be.
Click to expand...
That's a prime example of a chain reaction .. poor old '32 only had one real fault - even though it was all pointing towards the unobtainium ESP Module it was the burnt K40 that caused all the trouble and that module of course, has no codes of it's own 🤷‍♂️
 
#4 ·
Yes, that's what I meant (Stored, Not Current). But surely all these Stored, Not Current codes should show when I interrogate the relevant control unit?
 
R
#8 ·
I'm no expert on this, but a hypothesis: The CAN B is sending signals at, I think, 500k bps and therefore any interruption on the bus is going to be picked up. I'm thinking of maybe a slightly loose connector that's going to lose continuity for fractions of a second when you hit the bump. I've notice on my own Quick Test printout there are messages like "Fault in CAN communication with control unit EGS electronic transmission control" with a status like "Event STORED". That's in my IC module. I've not experienced any problems in that area. My thought is the has been a slight disruption to the signal that almost instantaneously righted itself?
 
#13 ·
@M4rCu5, would you mind explaining a bit more about 'events' in SDS. During my playing with the car, I can only find an option for events in the engine and transmission control units. These are the only control units that don't open DAS to view. The other control units, including the CCM and the VR use DAS and I can't find any option for events. Am I missing something?

DAS Simulation shows examples of the sort of events one can expect to find in the engine control unit. However, both my engine and transmission control units just say "No events present". So hardly worth posting any pdf files.

During my playing, I found that the CCM 'f' has disappeared and I now have a tick. My VR is still showing an 'f' and also the Gong fault code. Other folk with Smarttop have this fault code so I'm not concerned. I'm happy with things as they are and I will monitor future codes regarding my intermittent roof issue.

I'd still be interested in whether I can access 'events', for the VR control unit in particular, as the last roof event didn't produce any codes whatsoever, so 'events' might be useful.
 
#15 ·
You may well be right. I've just spent an hr going through mine in Simulation Mode and they are the only two places that events appear to be stored - I thought that they were stored in all but apparently that's not the case and we're limited on Events - Other modules use HHTWIN and as that's not available in Sim Mode so I canna check atm, but as stated Tone: You may well be right (y)
 
R
#14 · (Edited)
I don't have Simulation mode on mine. I think that's because I have the "passthru" version. Frankly, I get kinda reluctant to plug in, just incase I brick something, although I'm told that's almost impossible with passthru. So I tend to get in, do a quik test and then get out. I suppose over time I should get more adventurous! I do know that I have a couple of "!" items that the system tells me can't be cleared, so my hope of a "clean sweep board" is thwarted....
 
#16 · (Edited)
I am not that much "into" SDS but 2 things are into my mind EVENTS (think I saw it as a menu) - might be a thing for the specific edition you have!
And Rick - the❗mark is info read from the module is not correct/missing.
Airbags can not be made in 1901, yet the SDS showed it! So if possible charge the battery over night get into the module with ❗ and read the error(s) get back out and erase. Then read them ❗ again. As the low power may provide wrong feedback.
I am not saying is the case, just a general it shows 12.6 or above after you unlocked it and raised the bonnet - OK, if less - recharge - and or start it up for the test.
 
#17 ·
BaD_81 said:
I am not that much "into" SDS but 2 things are into my mind EVENTS (think I saw it as a menu) - might be a thing for the specific edition you have!
And Rick - the❗mark is info read from the module is not correct/missing.
Airbags can not be made in 1901, yet the SDS showed it! So if possible charge the battery over night get into the module with ❗ and read the error(s) get back out and erase. Then read them ❗ again. As the low power may provide wrong feedback. If I am not saying is the case, just a general it shows 12.6 or above after you unlocked it and raised the bonnet - OK, if less - recharge - and or start it up for the test.
Click to expand...
AB's made in 1901 still cracks me up :ROFLMAO: :ROFLMAO: :ROFLMAO:
 
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