LOCK 1C0155 - Caterpillar

Use this procedure in order to troubleshoot a low NOx conversion. Also, use this procedure if one of the following event codes is active or logged.
Table 1
J1939 Code and Description CDL Code and Description Comments
3516-15
Catalyst Reagent Concentration : High - least severe (1) N/A The Diesel Emissions Fluid (DEF) has a high concentration.
3516-17
Catalyst Reagent Concentration : Low - least severe (1) N/A The Diesel Emissions Fluid (DEF) has a low concentration.
4364-17
Aftertreatment #1 SCR Catalyst Conversion Efficiency : Low - least severe (1) E1309 (1)
Low Aftertreatment #1 SCR Catalyst Conversion Efficiency The NOx conversion across the SCR catalyst is lower than expected.
4364-18
Aftertreatment #1 SCR Catalyst Conversion Efficiency : Low - moderate severity (2) E1309 (2)
Low Aftertreatment #1 SCR Catalyst Conversion Efficiency The NOx conversion across the SCR catalyst is lower than expected. Probable Causes
Codes
DEF quality
Check software
DEF pump
DEF pressure line
Urea
SensorsRecommended Actions
Table 2
Troubleshooting Test Steps Values Results
1. Check for Codes
A. Connect Cat® Electronic Technician (ET) to the service tool connector.
B. Look for active codes that are associated with the system for the event code.
Codes
Result: An associated code is active.
Repair: Troubleshoot any associated codes before continuing with this test.
Result: An E1364, E1309, 3516, or 4364 code is active.
Proceed to Test Step 2
2. Check the DEF Quality
A. Using a 431-7087 Tool Gp, measure the Diesel Exhaust Fluid (DEF) quality.
Refer to Testing and Adjusting, "Diesel Exhaust Fluid Quality - Test" for the correct procedure.
25% to 42% DEF Concentration
Result: The DEF quality is NOT within the acceptable range.
Drain the DEF fluid from the tank. Refill the tank with DEF that meets ISO 22241 quality standards.
Proceed to Test Step 3.
Result: The DEF quality is within the acceptable range.
If the problem is not resolved, proceed to Test Step 3.
3. Check the Software Part Number
A. Turn the DC breaker to the ON position.
B. Connect Cat ET.
C. Check the aftertreatment ECM software part number in Cat ET.
Software Part Number
Result: The aftertreatment ECM software part number is 442-7939 SCR System Software 3500 or 440-0164 SCR System Software C175.
This version of software doses 1 L during the "Aftertreatment SCR System Dosing Test".
Proceed to Test Step 4.
Result: The aftertreatment ECM software part number is NOT 442-7939 SCR System Software 3500 or 440-0164 SCR System Software C175.
This version of software doses 2 L during the "Aftertreatment SCR System Dosing Test".
If the problem is not resolved, proceed to Test Step 5.
4. Check the DEF Pump
A. Turn the DC breaker to the OFF position.
B. Remove the DEF line that runs to the DEF injector from the dosing cabinet.
C. Run the DEF line into the container.
D. Turn the AC and DC breaker to the ON position.
E. Connect Cat ET.
F. Perform an "Aftertreatment SCR System Dosing Test" using Cat ET.
Note: While performing this test, the test hose can contain up to an extra 140 mL of fluid. If this fluid drains into the test container, the total volume of DEF will be 1145mL +/- 100 mL.
2 L (+/- 200 mL)
Result: The test returned 1 L +/- 100 mL of DEF.
Proceed to Test