Dummy Sensors / Testing

[Ludis Langens]

Bob Valentine wrote:
> 
> 1.  VATS bypass - is the signal "full wave", eg +2.5 / 0 / -2.5 ?

It should be either  "ground / open (ECM pulls to 5v) / ground / ..." 
or  "ground / 5v / ground / ...".  In some ECMs, the VATS input goes to
an input originally designed for a frequency MAF.

> 4.  On a '89 Firebird TPI schematic I have, the VSS input ("Speed Input")
> is shown going to a "VSS Buffer".  What's this?

The "VSS Buffer" converts the 4000 ppm magnetic pickup signal into an
open collector output at 2000 ppm.

-- 
Ludis Langens                               ludis (at) cruzers (dot) com
Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/