3364:1 - Aftertreatment Diesel Exhaust Fluid Quality - Data valid but below normal operational range - Most Severe Level

Contaminated DEF

Defective Sensor

1. The DEF sensor is detecting the fluid is not within the parameters of the software. If a refractometer is available, the fluid concentration can be verified. The concentration should be 32.5. If a refractometer is not available, go to step 2.

A. It is recommended to take multiple samples at different levels within the DEF tank. The sensor sets on the bottom of the tank, so a sample from the top of the tank may not give you an accurate reading of what the sensor is detecting. Draining a sample from drain plug would most likely give you the most accurate reading.

1. If the concentration is 32.5, replace the DEF sensor in the tank.

2. If the concentration is not 32.5, go to the next step.

2. When the DEF is determined to be the cause of the fault, the DEF system will need to be thoroughly cleaned. This will include draining and flushing the tank assembly and all three DEF lines. The DEF Pump filter will also need to be replaced to prevent further contamination. Use the "Useful Documents" at the bottom of this article for instructions on cleaning the system correctly.

3. After the DEF system has been cleaned according to the procedures, the machine can be started. Run the machine at idle for at least 30 minutes to give the system time to clear the faults.

A. If the faults do not clear after 30 minutes of running the engine, replace the DEF sensor assembly.

4. After replacing the DEF Sensor assembly, repeat step 3.