LOCK NUT 3B2037 - Caterpillar

Use this procedure in order to troubleshoot a low DEF tank temperature. 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
3031-1
Aftertreatment #1 DEF Tank Temperature : Low - most severe (3) N/A The DEF tank temperature is low.
3031-17
Aftertreatment #1 DEF Tank Temperature : Low - least severe (1) N/A The DEF tank temperature is low.
3031-18
Aftertreatment #1 DEF Tank Temperature : Low - moderate severity (2) N/A The DEF tank temperature is low.
Table 2
Associated Codes
J1939 Code CDL Code Troubleshooting Procedure
3363-5 3606-5 Troubleshooting, "Solenoid Valve - Test "
3363-6 3606-6 Troubleshooting, "Solenoid Valve - Test " Probable Causes
Codes
Temperature sensor
Check voltage
DEF tank heater
RelayRecommended Actions
Table 3
Troubleshooting Test Steps Values Results
1. Check for Codes
A. Turn the DC breaker to the ON position.
B. Establish communication between Cat® Electronic Technician (ET) and the Electronic Control Module (ECM).
C. Look for active codes that are associated with the system for the event code.
Diagnostic Code
Result: An associated code is present.
Repair: Troubleshoot any associated codes before continuing with this test.
Result: A 3031 code is present.
Proceed