Chart C1B - Crank Signal Check
Crank signal is a 12-volt signal to ECM during cranking to allow enrichment and cancel diagnostics until engine is running or 12 volts is no longer on circuit.
NOTE:
The following step numbers refer to the step numbers in the accompanying Flow Chart.
- Checks for normal (cranking) voltage to terminal 1 of ECM. Test light should be on during cranking.
- Checks to determine if source of blown fuse was faulty ECM.