PACCAR PX-9 CM2350 (2013-17) Fault Code:2353 PID:SID 146 SPN:2791 FMI:6 EGR Valve Control Circuit – Current Above Normal or Grounded Circuit

Reason:
EGR Valve Control Circuit – Current Above Normal or Grounded Circuit. A short circuit to ground has been detected in the EGR valve motor circuit.

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. 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 continuously when the keyswitch is in the ON position and the engine is running

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected a short circuit to ground in the EGR motor supply circuits.

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, 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:
N/A

Possible Causes:
1) One of the EGR motor circuits shorted to ground in the EGR valve motor
2) One of the EGR motor circuits shorted to ground in the harness
3) Malfunctioning ECM.