Cummins ISX12 CM2250 (2010-12) Fault Code: 6595 PID: SPN: 190 FMI: 11 Engine Speed- Root Cause Not Known

Circuit Description
The crankshaft position and camshaft position sensors are Hall effect type sensors. The engine control module (ECM) provides a 5 volt supply to the position sensor and a return circuit. As the teeth on the crankshaft speed ring or the dimples in the back of the camshaft gear move past the position sensor, a signal is generated on the position sensor signal circuit. The ECM interprets this signal and converts it to an engine speed. A missing tooth on the crankshaft gear is used by the ECM to determine the position of the engine.

Component Location
The crankshaft position and camshaft position sensor location varies, depending on engine model.

Conditions for Running the Diagnostics
This diagnostic runs continuously when the engine is running and during cranking.

Conditions for Setting the Fault Codes
The ECM detected a loss of both engine speed/position signals.

Action Taken When the Fault Code is Active
For On-Board Diagnostics (OBD) engines, the ECM illuminates the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.
Exhaust gas recirculation (EGR) valve operation will be disabled.
Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.
The engine may not start.
Conditions for Clearing the Fault Code
To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
The fault code status displayed by INSITE? electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
For OBD engines, the ECM will extinguish the MIL after three consecutive trips where the diagnostic runs and passes.
The ?Reset All Faults? command in INSITE? electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD engines.

Shop Talk
This fault code indicates the crankshaft position sensor and the camshaft position sensor have lost synchronization or the wiring harness connectors are reversed.

As a result, the engine will not start.

Possible Cause:
1) Battery Failure
2) ECM calibration