10d. Check RPM Signal While Cranking

10d. Check The RPM Signal While Cranking

Note: The scan tool may reset if the system voltage drops below 9.5 volts. You may need to use an outside voltage source for the scan tool.

Note: No FICM synchronization while cranking the engine with correct ICP RPM and VPWR signals usually indicates a loss of the CMP or CKP synchronization signal. Refer to the appropriate pinpoint test for diagnosis. Refer to Control System Diagnostic Sheet Reference for normal operating values.

Purpose:

This purpose of this test is to verify the CKP sensor the CMP sensor and related circuits are functioning.

Data List

Select the parameters indicated from the scan tool parameter list and monitor while cranking the engine.






Recommended Procedure:

^ Connect the scan tool.
^ Key ON engine OFF.
^ Monitor the RPM while cranking the engine.

Possible Causes:

^ Low battery voltage
^ High resistance in the starting system
^ Charging system
^ CKP sensor
^ CMP sensor

GO to Pinpoint Test D to diagnose a CKP concern.
GO to Pinpoint Test V to diagnose a CMP concern.

Tools Required:

Scan Tool