What the stepper outputs are
The stepper outputs are a set of four drivers. Unlike most ECU outputs, which can only switch to ground, these can drive either way: they can pull a wire up to 12V (high side) or down to 0V (low side), with up to 1 A of current. That flexibility is what lets them run stepper motors, which need their coils switched in a set sequence to move.
Driving an idle stepper
Many factory idle air valves are stepper motors, and the Elite's stepper outputs are designed to run both the 4-wire and 6-wire types. The four outputs connect to the motor's coil phases, and the ECU steps the valve open or closed to control idle speed. Once it's wired, set up and tune it using idle control and idle control tuning.
Using them as extra outputs
If the engine has a solenoid idle valve, or drive by wire with no idle valve at all, the stepper outputs aren't wasted. Each one can be assigned on its own to any function that needs a DPO (digital pulsed output), such as a fan relay, a shift light or a boost solenoid. Keep the 1 A limit in mind and use a relay for anything that draws more.
Ask us and we'll send it over with advice for your build.
Related: ignition outputs and fuel injector outputs.
