C3.4B Industrial Engine Caterpillar

The Selective Catalytic Reduction (SCR) system is a system used to reduce NOx emissions from the engine. Diesel Exhaust Fluid (DEF) is pumped from the DEF tank and is sprayed into the exhaust stream. The DEF reacts with the SCR catalyst to reduce NOx and leaves a nitrogen and water vapor.

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NOTICE
Stopping the engine immediately after the engine has been working under load can result in overheating of DEF system components. Refer to the Operation and Maintenance Manual, "Engine Stopping" procedure to allow the engine to cool and to prevent excessive temperatures in the turbocharger housing and the DEF injector.

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NOTICE
Allow at least 2 minutes after the engine has stopped before you turn the battery disconnect switch to OFF. Disconnecting the battery power too soon will prevent purging of the DEF lines after the engine is shut down.

Warning Strategy

The engine ECM will have software enabled in order to warn, derate, and only operate a low idle. This software is in order to keep the engine emissions complaint.

Warning Indicators

The warning indicators consist of a level gauge for the DEF, a low-level lamp for the DEF, an emission malfunction lamp, a warning lamp, a DEF quality lamp, and the application stop lamp.

The DEF level gauge will only give an accurate reading with the application on level ground.

Illustration 1	g03069862
(1) DEF Level gauge (A) Low-level warning lamp

Illustration 2	g02852336
Emission malfunction lamp

Warning Indicator Lamps

The warning indicator lamps can function in three different modes.

• On solid

• Slow flash (once a second)

• Fast flash (twice a second)

Warning Levels

Any warning should be investigated immediately, contact your Cat dealer. The system is equipped with an override option. Once the override option has been used and the fault still exist, the engine will be locked in de-rate at low idle only.

Override Option

The key switch can be cycled in order to give emergency power for 30 minutes.

• Turn on key switch for a minimum 5 seconds to a maximum of 15 seconds

• Turn off key switch for a minimum 5 seconds to a maximum of 15 seconds

• Turn on key switch for a minimum 5 seconds to a maximum of 15 seconds, then crank engine in order to start.

Inducement for low-level DEF

When low-level DEF inducement is active there is no override option to cycle the key switch.

Before engine operation, ensure that the DEF tank is full. Also, ensure that there is an adequate supply of DEF in order to refill the DEF tank.

Table 1

DEF in Tank Level
Warning Indicator	Stop Indicator	DEF Low Level Indicator	Emission Malfunction Indicator	DEF in Tank Level	Engine Power	Time	Comment	Action
OFF	OFF	OFF	OFF	-	Full Power	-	Normal Operation	None
OFF	OFF	On Solid	OFF	Less than 20 Percent	Full Power	-	Low DEF Indicator Active	Stop Engine and Fill DEF Tank
ON Solid	OFF	ON Solid	ON Solid	Less than Ten Percent	Full Power	-	Level 1 Indicators Active
ON Flashing Slowly	OFF	On Solid	ON Flashing Slowly	Less than Five Percent	Engine will Start to be Derated	Derate Timer Starts.	A Level 2 Inducement is Active
ON Flashing Fast	ON Solid	ON Flashing Fast	ON Flashing Fast	Empty Tank	Derate to engine Power	Start of 30 Minute Timer	A Level 3 nducement is Active
ON Flashing Fast	ON Solid	ON Flashing Fast	ON Flashing Fast		Engine will Only Operate at Low Idle.		A Level 3 Inducement is Active

Table 2

Inducement for Poor DEF Quality
Warning Indicator	Stop Indicator	DEF Quality Indicator	Emission Malfunction Indicator	Engine Power	Time	Comment	Action
OFF	OFF	OFF	OFF	Full Power	-	Normal Operation	None
On Solid	OFF	On Solid	On Solid	Full Power	Start of 50 Minute Timer	DEF Quality Out of Range Level 1 Inducement is Active	Stop Engine and Check DEF Quality. Refer to Systems Operation Testing and Adjusting, "Diesel Exhaust fluid Quality - Test" for More Information.
ON Flashing Slowly	OFF	ON Solid	ON Flashing Slowly	Start of Engine Derate	Start of 40 Minute Derate Ramp	A Level 2 Inducement is Active
ON Flashing Fast	ON Solid	ON Solid	ON Flashing Fast	Full Engine Derate. Low Idle (RPM) Only	At 210 Minutes	A Level 3 Inducement is Active

SCR System Inducements

Table 3

SCR System Inducements
Warning Indicator	Stop Indicator	Emission Malfunction Indicator	Engine Power	Time	Comment	Action
OFF	OFF	OFF	Full Power	-	Normal Operation	None
ON Solid or Slow Flashing (1)	OFF	ON Solid	Start of Engine Power Derate	Timer Starts, 240 Minutes Before Full Derate	A Level 1 Inducement is Active	Contact your Cat dealer . If a Code has been Activated Provide this Information to Your Dealer.
ON Flashing Slowly	OFF	ON Flashing Slowly	Derate to Engine Power and Speed		A Level 2 Inducement is Active
ON Flashing Fast	ON Solid	ON Flashing Fast	Full Engine Derate Low Idle (RPM) Only		A Level 3 Inducement is Active

(1)	Lamp mode will depend on the issue that has been identified.

NRS System Inducements

Table 4

NRS System Inducements
Warning Indicator	Stop Indicator	Emission Malfunction Indicator	Engine Power	Time	Comment	Action
OFF	OFF	OFF	Full Power	-	Normal Operation	None
ON Solid or Slow Flashing (1)	OFF	ON Solid	Start of Engine Derate	Timer Starts, 210 Minutes Before Full Derate	A Level 1 Inducement is Active	Contact your Cat dealer If a Code has been Activated Provide this Information to Your Dealer.
ON Flashing Slowly	OFF	ON Flashing Slowly	Derate to Engine Power and Speed		A Level 2 Inducement is Active

(1)	Lamp mode will depend on the issue that has been identified.