SEAL 0993209 - Caterpillar

Table 1
Diagnostic Trouble Codes for DEF Tank Level Is Low
J1939 Code CDL Code Code Description
(code descriptions may vary) Comments
1761-1 E954 (3) Aftertreatment #1 DEF Tank Volume : Low - most severe (3) This code is a Level 3 inducement that becomes active when the DEF tank is empty. The engine is derated 100%, limited to low idle or 1000 RPM, and may experience 5 minute rolling shutdowns.
1761-17 E954 (1) Aftertreatment #1 DEF Tank Volume : Low - least severe (1) This code is a Level 1 inducement that becomes active when the DEF level is critically low.
1761-18 E954 (2) Aftertreatment #1 DEF Tank Volume : Low - moderate severity (2) This code is a Level 2 inducement that becomes active when the DEF level is critically low. Power loss may occur.
Follow the troubleshooting procedure to identify the root cause of the problem. Refer to Systems Operation, "DEF Dosing Control System" for details on inducement configuration options and inducement actions for specific tank levels.Note: Always turn the keyswitch to the OFF position before adding DEF to the tank.Complete the procedure in the order in which the steps are listed.
Table 2
Troubleshooting Test Steps Values Results
1. Check the DEF Level
A. Turn the keyswitch to the ON position. Do not start the engine.
B. Check the current position of the DEF gauge.
C. Turn the keyswitch to the OFF position.
D. Clean dirt and debris from around the cap before removing the cap.
E. Fill the DEF tank to at least 25% capacity.
Note: Only use DEF that meets ISO 22241 quality standards.
F. Turn the keyswitch to the ON position.
G. Check for a change in the gauge position.
Gauge position
Result: The gauge did not move when DEF was added to the tank.
Proceed to Test Step 2.
Result: The gauge moved when DEF was added to the tank. Turn the keyswitch to the OFF position for 2 minutes to allow the DEF pump to purge, reset the code, and reset the Dosing Control Unit (DCU).
Return the unit to service.
Illustration 1 g03410399
(1) DEF Tank Header connector
(2) DEF Tank Header
Table 3
Troubleshooting Test Steps Values Results
2. Check the Electrical Connection at the DEF Tank Header
A. Inspect the electrical connector (1) to the DEF tank header. Refer to Troubleshooting, "Electrical Connectors - Inspect" for further information.
Look for corrosion or loose wires.
Electrical connections
Result: The electrical connectors are free of corrosion and are not loose.
Proceed to Test Step 3.
Result: The electrical connections are not free of corrosion and/or are loose.
Repair: Make the necessary repairs to the connectors. Turn the keyswitch to the OFF position for 2 minutes to allow the DEF pump to purge, reset the code, and reset the Dosing Control Unit (DCU).
Repeat the procedure from Test Step 1.
3. Inspect the DEF Tank Header
A. Turn the keyswitch to the OFF position.
B. Remove the DEF tank header (2) from the DEF tank. Refer to Disassembly and Assembly, "Manifold (DEF Heater) - Remove and Install".
C. If necessary, remove the filter sock from the DEF tank header.
C. Inspect the DEF tank header for a stuck float.
Correct operation of the