CM850 Electronic Control System – FAULT CODE 2273

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Overview

EGR Valve Differential Pressure Sensor Circuit SMALL | MEDIUM | LARGE

Circuit Description

The exhaust gas recircultion (EGR) differential pressure sensor has two ports that sense a pressure drop across the EGR gas entrance to the intake connection. The electronic control module (ECM) uses this pressure drop to calculate the amount of EGR gas entering the intake. This calculation helps to determine the commanded position of the EGR valve (and VG turbocharger)
that will control the amount of EGR gas flow into the engine.

Component Location

The EGR differential pressure sensor is mounted on the side of the intake air horn. Refer to Procedure 100-002 for a detailed component location view.

NOTE: The sensor is connected to the engine harness through a short pigtail harness. The pigtail harness is permanently affixed to the sensor. Do not try to remove the connector that is attached to the sensor body or damage to the sensor will occur.

Shop Talk

The EGR differential pressure sensor shares supply and return wires in the engine harness with other sensors. Open circuits and short circuits in the engine harness can cause multiple fault codes to be active. Before troubleshooting Fault Code 2273, check for multiple faults. Possible causes of this fault code include:

• Open return in the harness, connectors, or sensor
• Signal circuit shorted to sensor supply or battery voltage
• Supply circuit shorted to battery voltage.

Refer to Troubleshooting Fault Code t05-2273