CAT 3406E (Prefix 5DS or 1LW) Fault Code: 41 PID: 84 SPN: FMI: 0 Vehicle Overspeed Warning

The Engine Control Module (ECM) detects one of the following conditions:

•The “Soft Vehicle Speed Limit” parameter is programmed to “No” and the vehicle speed exceeds the programmed “Vehicle Speed Limit” by more than 10 MPH for more than 20 seconds.
•The “Soft Vehicle Speed Limit” parameter is programmed to “Yes” and the vehicle speed exceeds the programmed “Vehicle Speed Limit” by more than 15 MPH for more than 20 seconds.

Probable Causes:

1) ECM Programmed incorrectly
2) Speedometer is not reading engine speed correctly