Substitutions

[Ludis Langens]

Brent wrote:
> 
> The pin changes are second hand info.  I looked at the pinouts and found
> that C15 & D15 show as not used on the 7747.  I don't know where those pins
> lead in the 7747 if anywhere....
> In the 8746 I see D16 & D15 wired together as are D14 & C15.   Why they are
> linked that way I don't know.  I figured I should cut them to be safe.

The 8746 and 7747 use the same PCB.  Internal to the ECM, D14 and C15
are wired together.  Same with D15 and D16.  Pairing the pins increases
the current capacity.

> On the 8746 the A11 is cts,tps,mat gnd while the D2 is the map gnd.
> In the 7747 D2 is cts and tps gnd, and A11 is the map gnd.  Does this make a
> difference?  I don't know.  I figured if Gm could have used one ground pin
> they would have.

It won't make a bit of difference.  All the ECM's ground "outputs" are
equivalent.  Which one to use was probably determined by how the harness
was assembled and routed.

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

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