I've noted that Displayserver shows various power levels on it's web page, but I don't know where it's pulling that info from.

Displayserver is pulling that info from somewhere in the system, there's some sort of pipe or value you can read from to get that state. However, I don't know if there's a corresponding one for the headlight-sense line. Of course, if you think about it, there's got to be, right? It's just not written into displayserver right now.

Next question: Are you running the latest 1.02 software? I think I remember that 1.0 had some problems with certain headlight configurations.

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Tony Fabris