ISX15 CM2350 X101 Fault Code: 3237 | SPN: 4340 | FMI: 3 Aftertreatment 1 Diesel Exhaust Fluid Line Heater 1 Circuit Voltage Above Normal or Shorted to High Source Troubleshooting Summary 1 Aftertreatment diesel exhaust fluid line heater relay is malfunctioning 2 OEM wiring harness has a short to battery 3 Aftertreatment diesel exhaust fluid line heater is malfunctioning 3.1 Aftertreatment diesel exhaust fluid line heater resistance check 4 Aftertreatment diesel exhaust fluid line heater pin shorted to another pin 5 Aftertreatment diesel exhaust fluid line heater is malfunctioning 1 - Aftertreatment diesel exhaust fluid line heater relay is malfunctioning Solution: S00000796 Verification Conditions Turn keyswitch OFF. Disconnect the aftertreatment diesel exhaust fluid line heater relay from the OEM wiring harness. Action Inspect the pins and connectors for damage. Refer to Procedure 019-361 Check the relay. Refer to Procedure 019-642 Refer to the circuit diagram or wiring diagram for connector pin identification. Specification If the relay does not meet specification, then a malfunctioning relay has been detected. Linked Solutions None Repair Replace the aftertreatment diesel exhaust fluid line heater relay. Refer to OEM Service Manual Validation Connect all components Connect the recommended Cummins® electronic service tool or equivalent. Disable the fault code. Operate the engine within the "Conditions for Clearing the Fault Code" found in the Overview section of the troubleshooting procedure. Verify that the fault code is no longer active. Check ECM Calibration Revision History Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM. Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code. Refer to ECM Calibration Revision History Database. Next Solution 2 - OEM wiring harness has a short to battery Solution: S00001131 Verification Conditions Turn keyswitch OFF. Disconnect the aftertreatment diesel exhaust fluid line heater from the OEM wiring harness. Disconnect the aftertreatment diesel exhaust fluid line heater relay from the OEM wiring harness. Connect the OEM wiring harness to the ECM. Action Inspect the pins and connectors for damage. Refer to Procedure 019-361 Turn keyswitch ON. Measure the voltage between the aftertreatment diesel exhaust fluid line heater SIGNAL pin and the aftertreatment diesel exhaust fluid line heater RETURN pin at the aftertreatment diesel exhaust fluid line heater connector of the OEM wiring harness. Refer to the circuit diagram or wiring diagram for connector pin identification. Specification A malfunctioning OEM wiring harness has been detected if the voltage is within the following specification of battery voltage: 1 VDC Linked Solutions None Repair Repair or replace the OEM wiring harness. Refer to Procedure 019-071 Validation Connect all components Connect the recommended Cummins® electronic service tool or equivalent. Disable the fault code. Operate the engine within the "Conditions for Clearing the Fault Code" found in the Overview section of the troubleshooting procedure. Verify that the fault code is no longer active. Check ECM Calibration Revision History Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM. Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code. Refer to ECM Calibration Revision History Database. Next Solution 3 - Aftertreatment diesel exhaust fluid line heater is malfunctioning Solution: S00003290 Verification Conditions Turn keyswitch ON. Connect the recommended Cummins® electronic service tool or equivalent. Action Use the recommended Cummins® electronic service tool or equivalent to read the fault codes. Specification Proceed to the Linked Solutions section if a fault code from the following list is active or has more than one inactive count within the last 25 engine operating hours: 3237, 3239, 3422 Linked Solutions Aftertreatment diesel exhaust fluid line heater resistance check Refer to S00003291 Repair No additional action is required for this solution. Validation None Next Solution 3.1 - Aftertreatment diesel exhaust fluid line heater resistance check Solution: S00003291 Verification Conditions Turn keyswitch OFF. Disconnect the aftertreatment diesel exhaust fluid line heater from the OEM wiring harness. Action Inspect the pins and connectors for damage. Refer to Procedure 019-361 Measure the resistance between the appropriate aftertreatment diesel exhaust fluid line heater SIGNAL pin and the appropriate aftertreatment diesel exhaust fluid line heater RETURN pin at the appropriate aftertreatment diesel exhaust fluid line heater connector. Refer to the circuit diagram or wiring diagram for connector pin identification. Specification If the resistance is not between 2 Ω and 100 Ω, then a malfunctioning aftertreatment diesel exhaust fluid line heater has been detected. Linked Solutions None Repair Replace the aftertreatment diesel exhaust fluid line heater. Refer to OEM Service Manual Validation Connect all components Connect the recommended Cummins® electronic service tool or equivalent. Disable the fault code. Operate the engine within the "Conditions for Clearing the Fault Code" found in the Overview section of the troubleshooting procedure. Verify that the fault code is no longer active. Check ECM Calibration Revision History Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM. Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code. Refer to ECM Calibration Revision History Database. Parent Solution 4 - Aftertreatment diesel exhaust fluid line heater pin shorted to another pin Solution: S00000783 Verification Conditions Turn keyswitch OFF. Disconnect the aftertreatment diesel exhaust fluid line heater from the OEM wiring harness. Disconnect the aftertreatment diesel exhaust fluid line heater relay from the OEM wiring harness. Disconnect the OEM wiring harness connector from the ECM. Action Inspect the pins and connectors for damage. Refer to Procedure 019-361 Measure the resistance between the aftertreatment diesel exhaust fluid line heater SIGNAL pin at the OEM wiring harness ECM connector and all other pins in the OEM connector. Refer to the circuit diagram or wiring diagram for connector pin identification. Specification A malfunctioning OEM wiring harness has been detected if the resistance is less than the following specification: 100k Ω Linked Solutions None Repair Repair or replace the OEM wiring harness. Refer to Procedure 019-071 Validation Connect all components Connect the recommended Cummins® electronic service tool or equivalent. Disable the fault code. Operate the engine within the "Conditions for Clearing the Fault Code" found in the Overview section of the troubleshooting procedure. Verify that the fault code is no longer active. Check ECM Calibration Revision History Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM. Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code. Refer to ECM Calibration Revision History Database. Next Solution 5 - Aftertreatment diesel exhaust fluid line heater is malfunctioning Solution: S00003985 Verification Conditions Turn keyswitch OFF. Action Verify all preceding solution verifications for this fault code have been performed. Specification If the fault code is still active or inactive with more than one count within the last 25 engine hours and all the preceding solution verifications have been performed, then proceed to the Repair section. Linked Solutions None Repair Repair or replace only the components that were found to be out of specification. Replace the aftertreatment diesel exhaust fluid line heater. Refer to OEM Service Manual Validation Connect all components Connect the recommended Cummins® electronic service tool or equivalent. Disable the fault code. Operate the engine within the "Conditions for Clearing the Fault Code" found in the Overview section of the troubleshooting procedure. Verify that the fault code is no longer active. Check ECM Calibration Revision History Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM. Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code. Refer to ECM Calibration Revision History Database. If all steps have been completed and no root cause has been identified, then follow the technical escalation process. Table Of Contents Last Modified: 01-May-2022 Copyright © 2000-2010 Cummins Inc. All rights reserved.
