Revisions *always* in progress.

The Autronic SMC EMS requires electrical and/or physical connection to several components.  Before you attempt to install an EMS, you should take whatever steps you deem necessary to learn about electrical wiring so that you do not fry the SMC or cause a major electrical short or other problem for yourself.  The wiring colors in your engine harness and SMC wiring harness may be different than mine, so I strongly advise you to acquire the proper Toyota wiring diagram for your car before starting the install. 

Distributor	O2 Sensor
Idle Speed Control	Coolant Temp Sensor
Throttle Position Sensor	Air Temp Sensor
Map Sensor	Fuel Pump
Igniters & Coils	Fuel Injectors

The stock Toyota ISC is a three-wire unit.  However, aftermarket engine management systems are engineered to function with two-wire units.  As a result, the ISC remains installed but inoperable.  Even without the ISC, the engine idles quite well at 900-1000 rpms.  Some people indicate that they are content to not use an ISC while others feel it is a requirement.  I believe the SMC's idle tuning maps are providing a good measure of control over idle quality.  That said, I have constructed a small circuit which should allow the SMC to control the stock three-wire ISC.  However, should this not function as I desire, I will attempt to utilize one of the two used BWM two-wire ISCs I acquired from a friend who is a BMW mechanic.  Stay tuned.

The Autronic SMC has an internal is a 3-bar MAP sensor, which allows the SMC to measure boost pressures up to 2-bar, or roughly 28 psi, above atmospheric.  All that is required is the connection of a vacuum hose to the SMC unit from the intake manifold.  Since I mounted the SMC in the glove box next to the Greddy Profec-B Boost controller, I teed into the existing vacuum hose which runs to the Profec-B.  Easy easy!

The Autronic SMC controls operation of the fuel pump through the use of a relay on the SMC's wiring harness.  I merely wired the output from this relay to light blue/black wire feeding into connector block IE2, pin 19, which leads back to the fuel pump.

I installed and configured the Autronic SMC in The Shuttle to use sequential injection, which fires each fuel injector individually.  Ideally, each fuel injector should fire when its intake valve is open during the intake stroke, which is 90 degrees (measured at the distributor) before the sparkplug fires for that cylinder.  With a firing order of 1-3-4-2, the injectors are wired to fire in this same order, but advanced one position.  For example, cylinder 3 fuel injector fires simultaneously with cylinder 1 sparkplug.  Then, cylinder 4 fuel injector fires simultaneously with cylinder 3 sparkplug.  And so on.  The net effect is that the fuel is injected during the intake stroke which results in better fuel atomization and more power, or so goes generally accepted theory.

A fuel injector has on electrical connector with two pins.  It operates much like a relay in that when power is applied, a magnetic field is created to cause the injector to open.  And like a relay, the polarity of the energizing electricity is not important.  A respective wire from the Autronic SMC connects to one pin on the injector, and +12 vdc is applied to the other pin.  Again, the polarity applied to the injector pins does not matter.  However, for consistency sake, I wired like pins on each injector identically.

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