PWM in the currently planned scheme of things will probably upset the box (well, you'll get random stuff depending on wether the line is sensed high/low on the periodic poll by the empeg).

The line is a *lights on sense*, not a dash dimmer input. You can probably get round the problem by putting a bigish capacitor on the input to smooth out the PWM (I assume you mean PWM).

In theory, the empeg could support such a dimming scheme, except for the fact that my cars don't appear to do this, so I have no reference frame.

Hugo