Cummins ISB CM550 (1990-94) Fault Code: 297 PID: 223 SPN: 1084 FMI: 3 OEM Pressure Sensor Circuit

Circuit Description
The OEM sensor signal is used by the electronic control module (ECM) to monitor the OEM
pressure. The OEM pressure is used by the ECM in one of two ways:1. The ECM can shut
down the engine based on an OEM pressure input value exceeding or falling below a
customer-specified value.2. The ECM can control a device (dual-output driver A and driver B)
based on the value of the OEM pressure.A sensor that has failed high can be caused by an
open circuit in the signal or return wire, voltage shorts in the signal or return wire, or a faulty
sensor.

Component Location
The location varies with the OEM. Refer to the OEM manual.

Shop Talk
The sensor voltage signal is the responsibility of the OEM. Refer to the OEM manual for specifications.