Cummins ISB CM850 (2003-06) Fault Code: 1673 PID: SPN: 1761 FMI: 1 Catalyst Tank Level ? Data Valid but Below Normal Operational Range ? Most Severe Level. No catalyst solution has been detected in the catalyst solution tank.

Cummins ISB CM850 (2003-06) Fault Code: 1673 PID: SPN: 1761 FMI: 1 Catalyst Tank Level ? Data Valid but Below Normal Operational Range ? Most Severe Level. No catalyst solution has been detected in the catalyst solution tank.

Fault code 1673 is triggered when the catalyst solution level sensor has detected that the catalyst tank is empty. Catalyst solution may still be visible inside the tank when this fault code is active. Add catalyst solution to the tank.

On-Board Diagnostics (OBD) Information (Euro 4 Certified Engines):

1)The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2)The ECM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. The MIL lamp and fault code can also be cleared using the INSITE? service tool.
3)The fault code will be cleared from memory after 40 consecutive drive cycles where the diagnostic runs and passes.

On-Board Diagnostics (OBD) Information (Euro 4 Stage 1+ Certified Engines):

1)The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2)An engine torque derate will be activated after 50 hours of engine operation with the fault code active.
3)The ECM turns OFF the malfunction indicator lamp (MIL) after 1 ignition cycle that the diagnostic runs and does not fail. The MIL lamp cannot be cleared using the INSITE? service tool.
4)The fault code will be cleared from memory after 400 days or 9600 hours of engine operation.

Possible repairs:

1)Add catalyst solution to the catalyst solution tank.