MemCals Needing RFD Tweeking Before Finding A Home......

[Ludis Langens]

Walter Sherwin wrote:
> 
> 1)which trace was the RFD disabler in your case, and were there any
> ramifications from the computer "thinking" that the MEMCAL was missing?

I think it's what I call CAL45.  You may notice that there is a 10K
pullup on the ECM PCB for this signal.

> 2)when you bench run a P4 without NETRES's, I assume you still must find the
> moding pin(s) and arrange for a suitable voltage on same?

In my test ECM, the voltage defaults to about 2.5 volts.  That's right
on the boundary between two modes, but it always defaulted to the same
mode.  To try out other cylinder counts, I of course had to inject a
voltage into that circuit.

> 3)can a person physically disect the NETRES blocks so as to deduce the inner
> architecture, or is that simply impractical/impossible?

Once you start probing them, I think you'll find you don't need to
physically take them apart.  The construction will be simple enough.  If
you want to measure each resistance, that's possible despite the complex
circuits.  Measuring does however require two DVMs, a collection of
pots, and possibly a voltage source.  It's a classic EE black box problem.

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

----------------------------------------------------------------------------
To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org