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Home >> Ford >> 1990 >> Bronco II 4WD, Standard, M5OD-R1 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Test Aa - No Start (EDIS Ignition Only) >> Test Aa - Introduction
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Test Aa - Introduction

CAUTION: Stop this test at first sign of a fuel leak. DO NOT  allow smoking or an open flame in the vicinity of the vehicle during these tests.
NOTE: Enter this Pinpoint Test only when QUICK TEST have been successfully completed and the engine is still a no start, or when directed here from another test or chart.
NOTE: This test is intended to diagnose only the following EEC-IV ignition systems and circuits:
Fig 1: 4.0L MA PFI EDIS Module Circuits
G90D10952
EDIS TEST PIN IDENTIFICATION (WIRE COLOR)

Test Pin No. Wire Color
Pin 56
4.0L Aerostar Dark Blue
4.0L Bronco/Ranger Black/Light Blue

To prevent replacement of good components, be aware that the following non-EEC related areas and components may be at fault: