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Test N - Ignition Diagnostic Monitor (IDM): Notes

NOTE: Perform this test when Code 14, 18, 19, 28, 45, 46, 48 or 88 is displayed during QUICK TESTS or when directed here by other test procedure or driveability symptom. This test is intended to diagnose only the EEC-IV portion of the ignition system. For additional information on ignition system and component testing, see SYSTEMS & COMPONENT TESTING article.
NOTE: To prevent replacement of good components, be aware that the following non-EEC related areas may be at fault:
Fig 1: All Other TFI Applications
G90I13290
Fig 2: 3.0L SHO (DIS) IDM Circuit
G90B13293
TEST PIN WIRE COLOR IDENTIFICATION

Application (Test Pin No.) Wire Color
Pin 4, IDM
3.0L (California Only) Red/Light Blue
3.0L (Probe) Green
3.0L (SHO) Gray/Orange
All Others Dark Green/Yellow
Pin 16, IGN GND
3.0L (Probe) White
3.0L SHO Black/Orange
3.0L PFI (FWD) Gray
All Others Black/Orange
Pin 36, SPOUT/SAW
3.0L (Probe) Red
All Others Yellow/Light Green
Pin 56, PIP
3.0L (Probe) Black
All Others Dark Blue

There are 4 types of ignition system connections used with EEC-IV. They are configured as follows: