I have a 1990 560 SEL and have been doing some minor work to it. After having the passenger side air bag out repairing the heat, now the SRS light comes on when it feels like it. It doesn't just come on and stay on or come on in regular intervals. It just comes on when it feels like it, or sometimes not at all. I rechecked all the connections and even disconnected the battery again. Any ideas what it might be or where to look? Thanks!