PACCAR PX-9 CM2350 (2013-17) Fault Code:1896 PID:SID 146 SPN:2791 FMI:13 EGR Valve Controller – Out of Calibration

Reason:
EGR Valve Controller – Out of Calibration. The EGR valve has failed the automatic calibration procedure at initial key ON.

Effect:
Possible reduced engine performance

Circuit Description:
The exhaust gas recirculation (EGR) valve is controlled by a brushless motor located on top of the EGR valve. The EGR valve motor uses three different motor legs to move the valve through its range of motion. The ECM uses the EGR motor A, B, and C wires to command the EGR valve to the appropriate position in order to meet EGR flow targets.The EGR valve motor contains three position sensors that detect the location of the EGR valve. These sensors report the position of the valve back to the ECM over the EGR valve position A, B, and C wires.

Component Location:
The EGR Valve and EGR Differential Pressure Sensor location varies depending on engine model.

Conditions for Running the Diagnostics:
This diagnostic runs at initial key ON and occasionally during normal engine operation after the EGR valve is commanded closed.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the EGR valve failed the autozero span check.

Action Taken When the Fault Code is Active
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.
2) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
3) Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.

Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle and leave the key in the ON position for 2 minutes. Then start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
When the keyswitch is initially turned ON and at various times during engine operation, the closed position of the EGR valve is checked. This diagnostic checks to make sure the EGR valve is not stuck open. The EGR valve will close when the fault code is active. The fault code will remain active until the next key cycle. The aftertreatment system must be inspected after making the appropriate repair outlined in this fault code troubleshooting tree. Progressive damage to the aftertreatment system may have occurred. Perform the Snap-Acceleration Test to check for a malfunctioning diesel particulate filter.

Possible Causes:
1) Inactive fault codes
2) Faulty ECM