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Ignition System Identification

NOTE: For additional information and descriptions see IGNITION SYSTEMS in THEORY/OPERATION article in the ENGINE PERFORMANCE Section. Perform spark output check in BASIC TESTING article before entering these tests. Some ignition systems require that Quick Test procedure be performed prior to testing. This will retrieve trouble codes from the EEC-IV system. See TESTS W/CODES EEC-IV article.
IGNITION SYSTEM ACRONYMS (1)

Acronym Definition
BAT+ or BAT(+) Battery Positive
BAT or BAT(-) Battery Negative
BOB Breakout Box
CBD Closed Bowl Distributor (TFI-IV)
CCD Computer Controlled Dwell (TFI-IV)
CID Cylinder Identification
C1, C2, C3 Coil Drive (Coils 1, 2 & 3)
DIS Distributorless Ignition System
ECA Electronic Control Assembly (EEC-Processor, Computer, Processor)
EDIS Electronic Distributorless Ignition System
DPI Dual Plug Inhibit (High Signal - Rt Plugs Fire, Low Signal -Both Sides Fire)
IDM Ignition Diagnostic Monitor (Diagnostic Signal to ECA)
IGGND Ignition Ground (Low Current Ground Reference)
KOEC Key On Engine Cranking (Testing Condition
KOEO Key On Engine Off (Testing Condition)
KOER Key On Engine Running (Testing Condition)
PIP Profile Ignition Pickup (Crankshaft Sensor Signal)
PWRGND Power Ground Circuit to DIS Module
SAW Spark Angle Word
SPOUT Spark Output (ECA Spark Control Signal)
TFI or TFI-IV Thick Film Ignition (IV is 4th Generation)
VPWR or VBAT Battery Power or Battery Voltage
VRS or VR Sensor Variable Reluctance Sensor (Crankshaft)
(1) Not all circuits and components are used in all systems.
IGNITION SYSTEM IDENTIFICATION

Application System
2.3L Ranger DIS
2.9L Ranger TFI-IV
3.0L Aerostar & Ranger TFI-IV
4.0L Aerostar, Explorer, Navajo & Ranger EDIS
4.9L Bronco, "E" & "F" Series TFI-IV
5.0L Bronco, "E" & "F" Series TFI-IV
5.8L Bronco, "E" & "F" Series TFI-IV
7.5L "E" & "F" Series (1) TFI-IV
(1) Closed Bowl Distributor (CBD).