Cummins ISB4.5 CM2150 Fault Code: 1673 PID: 203F SPN: 1761 FMI: 1 Aftertreatment Diesel Exhaust Fluid Tank Level – Data Valid but Below Normal Operating Range – Most Severe Level.

Circuit Description
The aftertreatment diesel exhaust fluid level sensor is used to monitor the diesel exhaust fluid level inside the diesel exhaust fluid tank.

Component Location
The diesel exhaust fluid level sensor is located in the diesel exhaust fluid tank. Location of the tank and level sensor is OEM dependent.

Conditions for Running the Diagnostics
-This diagnostic runs continuously when the keyswitch is in the ON position.

Conditions for Setting the Fault Codes
-The aftertreatment diesel exhaust fluid level sensor has detected that the diesel exhaust fluid tank is empty.

Action Taken When the Fault Code is Active
-The ECM illuminates the amber CHECK ENGINE light and/or the malfunction indicator lamp (MIL) willl start to flash when the diagnostic runs and fails.
-An engine torque derate will be activated immediately when the fault code becomes active.

Conditions for Clearing the Fault Code
This fault code can not be cleared with INSITE™ electronic service tool.

-To validate the repair, start the engine and let it idle for 1 minute.
-The ECM will turn off the amber CHECK ENGINE lamp and/or MIL immediately after the diagnostic runs and passes.
-Use INSITE™ electronic service tool to verify the fault code is inactive.
-The inactive fault code will be cleared from the memory after 9600 hours of engine operation without a reoccurrence.

Shop Talk
Fault code 1673 is triggered when the diesel exhaust fluid level sensor has detected that the diesel exhaust fluid tank is empty. Diesel exhaust fluid may still be visible inside the tank when this fault code is active. Add diesel exhaust fluid to the tank.