P0409

WarningCooling

What This Code Means

Heavy unburnt fuel (soot) deposits in the EGR valve; EGR valve is not commanded to open; Fault codes set in the ECU during restart attempts (after shutdown of any type)

Possible Causes

•Light loading situations
•Small volume of air being used by the engine
•Insufficient volume of cooler or denser air to mix with exhaust from the EGR without negatively affecting engine performance
•Continuous operation of the unit under light load

Suggested Actions

1Remove the EGR valve (disconnect one electrical plug and 7 bolts) to clean off the soot deposits (Note: Gaskets can be reused)

Related Multiquip Fault Codes

REFILL DEF SCR FORCED PURGE P0404 SCR FORCED PURGE ACTIVE OVERSPEED SHUTDOWN SCR PURGE ACTIVE OVERSPEED ALARM SPN 2659 FMI 1 OVERSPEED SPN 2659 FMI 18 OVERCRANK SHUTDOWN WATER TEMPERATURE ALARM LAMP

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