Fault Code 174: Engine Default Torque Limit
J1939: SA 3 SPN 1846 FMI 12, 13, 19
Overview
The Transmission Control Module (TCM) sends and receives Engine Default Torque Limit (EDTL) messages to and from the engine Electronic Control Unit (ECU) over the Primary Data Link (J1939A). This message is used by the TCM to confirm the Engine ECU is receiving and responding to the default torque limit.
Detection
The TCM monitors EDTL messages. If messages are not available or are invalid, the fault is set Active.
Conditions to Set Fault Code Active
FMI 12 – Bad Intelligent Device: EDTL message does not match SPN 1845 – Transmission Torque Limit (TTL) message for 30 seconds.
FMI 13 – Out Of Calibration: EDTL message not available for 30 seconds.
FMI 19 – Received Network Data In Error: EDTL messages invalid for 30 seconds.
Fallback
FMI 12, 13, 19:
- Amber warning lamp on
- No degraded modes
Note: Vehicle may have additional fallback modes. Refer to OEM.
Conditions to Set Fault Code Inactive
FMI 12: EDTL and TTL messages match for 10 seconds.
FMI 13, 19: EDTL messages available and valid for 10 seconds.
Possible Causes
FMI 12, 13, 19:
- Vehicle Components
- Engine Default Torque Limit message not enabled
- Engine ECU software configuration incompatible
- Engine ECU internal failure
- Other vehicle ECU(s) faulted
- Vehicle Harness - Primary Data Link (J1939A)
- Wiring shorted to power, shorted to ground or open
- Terminals bent, spread, corroded, or loose
Note: Refer to OEM for troubleshooting a failed system.
Additional Tools
- None
Fault Code 174 Troubleshooting
Set vehicle parking brake and chock wheels.
Record transmission fault codes, FMIs, occurrences, and timestamps from Service Activity Report created during the Diagnostic Procedure.
If Fault Code 174 is Inactive and there are other Active vehicle or transmission fault codes, troubleshoot all Active fault codes. Go to Step V
If Fault Code 174 FMI 12 is Active or Inactive, Contact Eaton Cummins Automated Transmission Technologies for further diagnostic instructions. For Help Line phone numbers, go to Contact Information. Go to Step V
If Fault Code 174 FMI 13 is Active, refer to OEM and enable vehicle Engine Default Torque Limit message (SPN 1846). Go to Step V
If Fault Code 174 FMI 13 is Inactive, Go to Step V
If Fault Code 174 FMI 19 is Active or Inactive, refer to OEM guidelines for repair of the vehicle Engine Default Torque Limit message (SPN 1846). Go to Step V
Key off.
Reconnect all connectors and verify all components are properly installed.
Key on with engine off.
Connect ServiceRanger.
Go To “Fault Codes”.
Select “Clear All Faults”.
Operate vehicle and attempt to reset the fault code or duplicate the previous complaint.
Check for fault codes using ServiceRanger.
If no fault codes set and vehicle operates properly, test complete.
If Fault Code 174 sets Active, Go to Step A
If a fault code other than 174 sets Active, Fault Code Isolation Procedure Index.