*Important Note-Before starting the diagnosis process, verify that the ECM calibration is up to date. An outdated ECM calibration can lead to issues with sensors and modules.
Test the EGR differential pressure sensor circuit by connecting a jumper wire between the SUPPLY and SIGNAL pins at the sensor connector in the engine wiring harness. If this triggers code 2273, the sensor is faulty. If not, continue to next step.
Measure the voltage between the SUPPLY and RETURN pins of the EGR differential pressure sensor at the engine wiring harness connector. If the voltage is not 5 volts, check the voltage at the ECM.
To check the ECM, disconnect the engine wiring harness and measure the voltage between the SUPPLY and RETURN pins of the EGR differential pressure sensor at the ECM. If the voltage at the ECM is not 5 volts, the ECM is faulty. If the voltage at the ECM is 5 volts, the issue is likely with the engine wiring harness. To test the sensor circuit at the ECM, connect a jumper wire between the SUPPLY and SIGNAL pins at the ECM. If code 2273 is triggered, the engine wiring harness is faulty. If code 2273 is not triggered, the ECM is faulty.
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