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Ignition System - HEI/Est/ESC
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Ignition System - HEI/Est/ESC
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Description
High Energy Ignition (HEI)
HEI With Electronic Spark Timing (Est)
HEI-Est With Electronic Spark Control (ESC)
HEI With Electronic Spark Control (ESC)
Integral Ignition Coil
Remote Ignition Coil
Operation
HEI-Est (Except "S" & "T" Truck W/2.5L)
Notes
Terminal "A" - REF LOW
Terminal "B" - BYPASS
Terminal "C" - REF
Terminal "D" - EST
HEI-Est (Only "S" & "T" Truck W/2.5L)
Notes
Terminal "A" - EST
Terminal "B" - REF
Terminal "C" - BYPASS
Terminal "D" - REF LOW
HEI-ESC System
HEI-Est-ESC System
Diagnosis
All HEI/HEI-Est (Except "S" & "T" Truck W/2.5L)
HEI/Est On "S" & "T" Truck W/2.5L Only
HEI-ESC
HEI-Est-ESC
Component Testing
Electronic Module (HEI)
Ignition Coil (HEI)
Pick-Up Coil (HEI)
Capacitor (HEI)
External Coil Resistance Check (HEI-Est)
External Mounted Coil (Sealed Module Connector Distributor)
Integral Coil Resistance Check (HEI-Est)
Integrally Mounted Ignition Coil
Pick-Up Coil Short & Resistance Checks (HEI-Est)
"S" & "T" Truck W/2.5L Only (HEI-Est)
Hall Effect Switch
Overhaul
Wiring Diagrams