Cummins ISB4.5 CM2150 Fault Code: 545 PID: SPN: 1188 FMI: 7 Turbocharger 1 Wastegate Control – Mechanical System Not Responding or Out of Adjustment.

Posted by PerDiezel Solutions on January 20, 2026

Circuit Description
The intake manifold pressure sensor is used by the engine control module (ECM) to monitor the engine intake manifold pressure.

Conditions for Running the Diagnostics
This diagnostic runs continuously when the keyswitch is in the ON position.

Conditions for Setting the Fault Codes
This fault code becomes active when the intake manifold pressure exceeds the maximum pressure limit for a given engine rating.

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

Conditions for Clearing the Fault Code
-To validate the repair, start the engine and let it idle for 1 minute.
-The ECM will turn off the amber CHECK ENGINE light and the fault code will go inactive immediately after the diagnostic runs and passes.
-This fault code can also be cleared with INSITE™ electronic service tool.

Possible Causes
-Malfunctioning turbocharger wastegate
-Wastegate tampering
-Wrong turbocharger part
-Possible tampering of the fuel system or turbocharger system.

Cummins ISB4.5 CM2150 Fault Code: 527 PID: SPN: 702 FMI: 3 Auxiliary Input/Output 2 Circuit – Voltage Above Normal or Shorted to High Source.

Cummins ISB4.5 CM2150 Fault Code: 499 PID: 98 SPN: 98 FMI: 4 Engine Oil Level Sensor Circuit – Voltage Below Normal or Shorted to Low Source.

Cummins ISB4.5 CM2150 Fault Code: 498 PID: 98 SPN: 98 FMI: 3 Engine Oil Level Sensor Circuit – Voltage Above Normal or Shorted to High Source.

Cummins ISB4.5 CM2150 Fault Code: 492 PID: SID 88 SPN: 1189 FMI: 4 Turbocharger 2 Wastegate Control Circuit – Voltage below normal, or shorted to low source.

Cummins ISB4.5 CM2150 Fault Code: 491 PID: SID 88 SPN: 1189 FMI: 3 Turbocharger 2 Wastegate Control Circuit – Voltage Above Normal or Shorted to High Source.

Cummins ISB4.5 CM2150 Fault Code: 478 PID: 444 SPN: 444 FMI: 0 Battery 2 Voltage – Data Valid but Above Normal Operating Range – Moderately Severe Level.

WARNING!