Cummins ISB4.5 CM2150 Fault Code: 2345 PID: 103 SPN: 103 FMI: 10 Turbocharger 1 Speed – Abnormal Rate of Change.

Circuit Description
The turbocharger speed sensor is a variable reluctance speed sensor. It consists of a coil of wire and an iron core. The target on the turbocharger shaft is a ground flat in the center of the shaft. As the flat on the turbocharger shaft passes the speed sensor, a signal is generated. The engine control module (ECM) interprets this signal and converts it to a turbocharger speed reading.

Component Location
The turbocharger speed sensor is located in the center housing of the turbocharger.

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

Conditions for Setting the Fault Codes
The ECM detects that the turbocharger speed has increased faster than physically achievable by the turbocharger.

Action Taken When the Fault Code is Active
-The ECM illuminates the amber CHECK ENGINE light immediately when the diagnostic runs and fails.
-The ECM will estimate turbocharger speed.

Conditions for Clearing the Fault Code
The ECM will turn off the amber CHECK ENGINE light immediately after the diagnostic runs and passes.

Shop Talk
This fault code can be caused by an intermittent turbocharger speed sensor connection, incorrect turbocharger speed sensor air gap, or a malfunctioning turbocharger speed sensor.