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Home >> Ford >> 1990 >> Probe GT, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 2.2L >> Test D3 - Self Test Input (STI)/Self Test Output (STO) >> Self Test Input (STI)
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Self Test Input (STI)

NOTE: Enter this test only when Star Tester displays STO LO or VOM displays zero volts.
STI CIRCUIT PIN IDENTIFICATION

Circuit Breakout Box Pin ECA Pin
2.2L MTX Non-Turbo STI 48 1K
2.2L Except MTX Non-Turbo STI 48 1I

1) Checking System Integrity  Visually check all wiring and connectors for evidence of damage, shorting or looseness. If a fault is found, repair as necessary. If no faults are found, go to next step.

2)  Install breakout box and leave ECA disconnected. Connect test light between STI test pin and 12 volt source. If light does not comes on, repair circuit between STI connector and ECA. If light does come on, go to SELF TEST OUTPUT (STO).