How about an "eye" (not sure what this would technically be) that's
positioned to "watch" the cluster of indicator lamps and trigger the
buzzer when a red one illuminates?

Allan

Mike S <mikes@FLATSURFACE.COM> writes:

> At 07:55 PM 12/16/2009, Richard Koerner wrote...
>>What we need is a simple fix.  A small "box" of electronics, wired in
>>so as to detect any of the red LED's coming on (oil pressure,
>>alternator, coolant temperature), with a LOUD piezo speaker blasting
>>you to "get OFF the road and shut down IMMEDIATELY!!!.   Doesn't have
>>to speak words....just be obnoxious.
>
> Depending on the individual circuit, a warning lamp might be triggered
> by a wire going high (other side of the lamp is always grounded), or by
> a switch to ground (other side of the lamp is always +12V). Both can be
> combined in a "wired-or" by using a diode for one type, a transistor
> for the other. Then just send the combined signal to a piezo buzzer,
> like a Sonalert. <$10 in parts.
>
> (BTW, this is hardly EE level stuff)
>

--
1991 Vanagon GL