Cummins ISB4.5 CM2150 Fault Code: 1671 PID: 203F SPN: 1761 FMI: 18 Aftertreatment Diesel Exhaust Fluid Tank Level – Data Valid but Below Normal Operating Range – Moderately Severe Level.

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

Component Location
The diesel exhaust fluid tank 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
Low aftertreatment diesel exhaust fluid level has been detected in the diesel exhaust fluid tank.

Action Taken When the Fault Code is Active
The ECM illuminates the amber CHECK ENGINE light and/or the malfunction indicator lamp (MIL) immediately when the diagnostic runs and fails.

Conditions for Clearing the Fault Code
-To validate the repair, start the engine and let it idle for 1 minute
-The ECM will turn off the amber CHECK ENGINE light immediately after the diagnostic runs and passes.
-The ECM will turn off the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and passes.
-This fault code and malfunction indicator lamp (MIL) can also be cleared with INSITE™ electronic service tool.

Shop Talk
Fault code 1671 is triggered when low diesel exhaust fluid level has been detected in the diesel exhaust fluid tank. Add diesel exhaust fluid to the tank. This fault code is only a warning for low diesel exhaust fluid tank solution level.