Voltage trigger questions for 95 C280
 

I've got an ongoing SRS light on my car... and have been told my charging system has been weak.
My car is currently getting a new alternator. The MB dealer told me (few weeks ago) that my SRS light wouldn't clear, therefor my SRS module needs to be replaced... I beg to differ.

I have a question...

At what voltage level is the SRS disabled (triggering the SRS light)?

At what voltage level is the ABS disabled?

What electronics, and how, trigger the battery (charging system problem) light? In other words, how does this particular system know/monitor the trigger of the battery light (in the cluster)?
Hope that made sense.

Thanks for the help!