Car 1994, stock. Iím installing MS slowly and (hopefully) methodically by way of the schematics here
and Brainís hugely helpful MS how-to.
The original goal was to go standalone since I have no A/C. In place are the miata ignition mods, the fan mod and the IAC transistor.
The following is a list of circuits that are wired to the stock ecu and would not be accounted for (or operated by) a standalone MS, as far as I can see in the available documentation.
Things I donít care about
EGR vent solenoid
EGR vac. solenoid
EGR function sensor
charcoal can purge
rear defrost relay
* vehicle speed sensor (whatís this? a/t only?)
steering pressure sensor
The well documented items:
condenser fan relay (a/c)
refrigerant pressure switch (a/c)
* The items which seem important to me but Iím not clear about (the reason for my post):
heater control unit (whatís this do?)
pressure regulator control solenoid (fuel pressure drop at idle?)
malfunction indicator (cel?)
TNS relay (wtf is this?)
3 (of 6) wires at the data link connector not accounted for
main fuse block (+12 to ecu) 1C violet wire (the only indicated hot lead in the MS docs seems to be the ecu-controlled +12 wht/red)
Iím starting to think parallel is the better strategy.
* Is there ANY degradation of signal accuracy when the signals (low voltage) are shared by two ecuís? Just making sureÖ.
* Would it be fair to assume there would be zero drawbacks to running parallel units?
* = my questions
Thanks again for everyoneís help