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Home >> Chevrolet >> 1986 >> Astro Van M V6-262 4.3L >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Cranking Signal >> Testing and Inspection
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Cranking Signal: Testing and Inspection

Chart C-1B - Crank Signal:




Wiring Diagram For Chart C-1B - Crank Signal:






CHART C-1B - CRANK SIGNAL

Circuit Description:

Crank signal is a 12V signal to the ECM during cranking to allow enrichment and cancel diagnostics until engine is running or 12V is no longer on circuit.



Test Description:

1. Checks for normal (cranking) voltage to terminal "C9" of ECM. Test light should be "ON" during cranking.



2. Checks to determine if source of blown fuse was a faulty ECM.

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