C-1B ~ Engine Crank Signal

Chart C-1B Chart C-1B - Crank Signal Diagnosis:

Chart C-1B - Crank Signal Diagnosis:

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

TEST DESCRIPTION
Numbers below refer to circled numbers on the diagnostic chart.
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 or fuse link was a faulty ECM.