11 May, 2025Cummins ISB4.5 CM2150 Fault Code: 452 PID: SPN: 157 FMI: 4 Injector Metering Rail 1 Pressure Sensor Circuit – Voltage Below Normal or Shorted to Low Source. Share on Facebook Opens in a new window. Tweet on Twitter Opens in a new window. Pin on Pinterest Opens in a new window. Back to blog