SPN 2791 - FMI 7 (Fault Code 2357)
SPN2791 FMI7
EGR Valve Control Circuit - Mechanical System Not Responding Properly or Out of Adjustment
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| ISB, ISC, and ISL - EGR Valve Circuit |
Fault Code: 2357
PID(P), SID(S): S146
SPN: 2791
FMI: 7/7
Lamp: Amber
REASON: EGR Valve Control Circuit - Mechanical System Not Responding Properly or Out of
Adjustment. The EGR motor has exceeded the duty cycle limit, indicating a stuck open EGR valve.
EFFECT: EGR valve actuation will be disabled.
Circuit Description:
The exhaust gas recirculation (EGR) valve is opened by a motor located on top of the EGR valve. A motor shaft extends from the motor and contacts the dual-poppet valve to open the EGR valve. The EGR valve motor does not actually retract the EGR valve. The motor current is reduced and the spring pushes the EGR valve closed.
Component Location:
The EGR valve location can vary, depending on the engine application.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.
Conditions for Setting the Fault Codes:
This fault code is set when the duty cycle required to open the EGR valve is greater than 95 percent for 3 seconds. The EGR valve controller will try to open the EGR valve again after 10 seconds. The fault code is triggered after three failed attempts.
Action Taken When the Fault Code is Active:
• The ECM illuminates the amber CHECK ENGINE light immediately when the diagnostic runs and fails.
• The EGR valve will stop responding to commands and the spring will close the EGR valve.
Conditions for Clearing the Fault Code:
The ECM will turn off the amber CHECK ENGINE light and clear the fault code after the keyswitch is cycled and the diagnostic runs and passes. The fault code will be inactive at key-on. It will only go active if the EGR valve is commanded open and the EGR valve is unable to move to the commanded position.
Shop Talk:
Verify the electronic control module (ECM) calibration is correct. Check the calibration revision history found on QuickServe™ Online for applicable fixes to the calibration stored in the ECM.
This fault code is triggered when the EGR valve motor is unable to move the EGR valve in the open position. This is normally caused by a restriction in the EGR valve not allowing the EGR valve to move to the commanded position.
The fault code will be inactive at key-on. It will only go active if the EGR valve is commanded open and the EGR valve is unable to move to the commanded position.
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 aftertreatment initial check procedure to test for a damaged diesel particulate filter (DPF).
Possible causes of this fault code include:
• Fuel Injector wiring harness shorted to ground, open circuit, or shorted to power supply.
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