The engine idle will increase when the ECU enters KEOR mode. Connect this to the ground pin directly below it. The STI Input is the first pin on the top left of the connector on the EBII-EL. With the engine running, connect the Engine STI Input on the diagnostic connector to ground.The steps to get into this mode are as follows: Getting into KOER Diagnostic / Base Timing modeīase timing is set after the Key On Engine Running (KOER) diagnostic tests are completed. Write down the codes on a piece of paper, which will be displayed as flashes of the light/buzzer/meter in the following sequence:.Turn the Ignition Switch to On, but do not start the engine.The STO Pin is the 5th Pin from the left on the upper row on the EBII-EL. Connect an LED, Analog Multimeter, or Buzzer between the STO Pin and Ground.With the Ignition Switch Off, connect the Engine STI Input on the diagnostic connector to ground.This guide will focus on the Key On Engine Off (KOEO) diagnostic mode, which provides the most useful info. The STO is pin 4 of the 6 pin diagnostic connector the EA, or the 5th pin on the EBII-EL connector. The STI is the single pin connector on the EA, or the top left pin on the EBII-EL. STI/STO – The Self Test Input (STI) and Self Test Output (STO) pins are used to enter diagnostic mode and read the output codes respectively.This guide only covers the KOEO test which is most helpful for reading stored codes. These include – Key On Engine Off (KOEO), Key On Engine Running (KOER), Fan Test (EF/EL Only), Balance Test (V8 only), and Wiggle Test. EEC Diagnostic Modes – There are a number of diagnostic modes in the ECU.Location and pinout of diagnostic connectors for EA-EL Ford Falcon Ignition System & Performance Ignition Parts.