Cummins ISB4.5 CM2150 Fault Code: 2374 PID: 131 SPN: 1209 FMI: 4 Exhaust Gas Pressure Sensor Circuit – Voltage Below Normal or Shorted to Low Source.

Circuit Description
The exhaust gas pressure sensor is used to measure exhaust gas pressure in the exhaust manifold. This information is used by the engine control module (ECM) to control emissions and exhaust gas recirculation (EGR) valve operation. The ECM provides a 5 volt supply to the exhaust gas pressure sensor on the sensor supply circuit. The ECM also provides a ground on the sensor return circuit. The exhaust gas pressure sensor provides a signal to the ECM on the exhaust gas pressure sensor signal circuit. This sensor signal voltage changes based on the pressure in the exhaust manifold.

Component Location
The exhaust gas pressure sensor is located above the front section of the exhaust manifold and is plumbed into the exhaust manifold.

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

Conditions for Setting the Fault Codes
The ECM detects that the exhaust gas pressure signal voltage is less than .25-VDC for more than 4 seconds.

Action Taken When the Fault Code is Active
-The ECM illuminates the amber CHECK ENGINE light immediately when the diagnostic runs and fails.
-A default value of the exhaust gas pressure reading is used.

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
The exhaust gas pressure sensor shares supply and return wires in the engine harness with other sensors. Opens and shorts in the engine harness can cause multiple fault codes to be active.

Possible Causes
-A signal circuit open or shorted to ground in the engine harness or sensor
-A SUPPLY wire open or shorted to ground.