Airbag malfunction

First of all, hello everyone.
I'm new to this forum and already have a question.

In my Audi A6 2.5 TDI, manufactured in 11/1999, the airbag warning light illuminates upon starting the engine, after approximately 8 hours of standstill. After about 30 seconds, it starts blinking and then turns off completely. This problem only occurs when the temperature is below 6°C; the colder it is, the longer the light remains on. The error memory scan did not show any errors. Could it be that the airbag electronics become sluggish at low temperatures, or does anyone have a tip for me as to what else it could be?
The specialist workshop hasn't been able to help me so far, and they said that after a long search (which could be expensive), the problem might not be found.

'Marr' translates to 'Marr' in English. It's likely a name or a word with a specific meaning in the original context. Without more information, it's impossible to provide a more accurate translation.

I once looked at Audi's troubleshooting guides, and nothing like that is mentioned there.

To the best of my knowledge, any error that the system attempts to signal through the warning light should also be stored in the error memory (and, given the safety-critical nature of the airbag system, it should be stored with a higher priority).

I can't quite picture how the error reading process works...

On the other hand, I also believe that in safety-critical systems (such as airbags and ABS), the warning light should remain illuminated after a single fault detection until the ignition is turned off.

Conclusion: The error is completely inexplicable to me. I'd like to see what others have to say about it. If no one says anything, I personally suspect there's a strange issue with the control unit.

Thank you very much for your quick response.

'This morning, and also last week, my car stalled at my Audi specialist workshop, but no error codes were displayed! I had this problem earlier in the year during the colder months, but I didn't pay much attention to it then. Then spring arrived, it got warmer, and the airbag light turned off immediately after starting the engine, as it should.'
Now that winter is here again, the old problem is back to haunt me.
As I said:
At 6 degrees Celsius, the light turns on for approximately 30 seconds, then starts blinking, and then turns off.
At 0° Celsius, the light turns on for approximately 50 seconds, then starts blinking, and finally turns off.
Above 6°C, the light will immediately turn off after the engine is started.

I had already considered moving to warmer regions .
But first, I need to win the lottery jackpot on Saturday.

'Marr' translates to 'Marr' in English. It's likely a name or a word with a specific meaning in the original context. Without more information, it's impossible to provide a more accurate translation.

Based on my experience, if there's a fault in the airbag system, it's stored in a way that would cause the airbag warning light to stay on continuously. If it's not burning, it probably doesn't have a problem.
With ABS, things are different; the error disappears, and the light goes out.

Here's my guess:

Could the blinking indicate a low voltage condition?
Perhaps it would also explain why no error code is stored, as it is a 'normal operating state after engine start.'
It's possible that the preheating/afterglow function only activates above 6°C, which is why the error doesn't occur in the summer.
There's something similar offered by DB for rear window defrosters. The indicator light also blinks when the voltage is too low, and the HSH (presumably a device or system) is not functioning.
Otherwise, the graphics card might be defective, although this is quite rare.

As I said, I'm not even sure if this feature exists in these vehicles.

Hello,
I don't think the underlying cause is undervoltage, because wouldn't there be an error message displayed?
However, there is a voltage indicator on the dashboard, which shows the full voltage approximately 7 seconds after the engine starts.
I still believe it's due to a faulty connection (water/corrosion or something similar).
Where is the SG (Steuergerät - control unit) located in the Audi A6?

'Marr' translates to 'Marr' in English. It's likely a name or a word with a specific meaning in the original context. Without more information, it's impossible to provide a more accurate translation.

Hello,
I don't think the underlying cause is undervoltage, because wouldn't there be an error message displayed?
However, there is a voltage indicator on the dashboard, which shows the full voltage approximately 7 seconds after the engine starts.


Measure the voltage directly after starting the engine, using a multimeter connected to the battery. That sounds like a minor power supply issue to me as well.

Hello!

Found one more post!
So, I'm not the only one with these "unusual" errors...

I'd be interested to know what Marr was able to identify as the cause.


Best regards: Marko