Cummins ISB4.5 CM2150 Fault Code: 3565 PID: SPN: 5394 FMI: 3 Aftertreatment Diesel Exhaust Fluid Dosing Valve – Voltage Above Normal or Shorted to High Source.

Posted by PerDiezel Solutions on January 20, 2026

Circuit Description
The aftertreatment diesel exhaust fluid (DEF) dosing valve is controlled by the aftertreatment DEF controller. When the engine electronic control module (ECM) commands DEF dosing, the DEF controller sends a pulse width modulated (PWM) signal to the dosing valve, which opens the dosing valve and allows DEF to be sprayed into the exhaust stream.

Component Location
The aftertreatment diesel exhaust fluid dosing valve is installed in the exhaust system. It is mounted directly to the aftertreatment decomposition tube, before the SCR catalyst. Installation position will vary, based on the aftertreatment architecture and the original equipment manufacturer (OEM).

Conditions for Running the Diagnostics
This diagnostic runs when the diesel exhaust fluid dosing valve is being commanded on.

Conditions for Setting the Fault Codes
The aftreatment diesel exhaust fluid controller detects that the diesel exhaust fluid dosing valve voltage is above a calibratible value.

Action Taken When the Fault Code is Active
-The ECM illuminates the amber CHECK ENGINE lamp and/or the malfunction indicator lamp (MIL) immediately when the diagnostic runs and fails.
-Diesel exhaust fluid injection into the aftertreatment system is disabled.
-Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.

Conditions for Clearing the Fault Code
-To validate the repair, diesel exhaust fluid dosing must be commanded so that the dosing valve is actuated. This can be done by performing the “Aftertreatment Diesel Exhaust Fluid Doser Pump Override Test” found under “ECM Diagnostic Tests” in the INSITE™ electronic service tool.
-The fault code status displayed by the INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
-The ECM will turn off the amber CHECK ENGINE lamp after the diagnostic runs and passes.
-For OBD engines, the ECM will turn off the MIL after 3 consecutive trips where the diagnostic runs and passes.
-The “Reset All Faults” command in the INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Possible Causes
-Short to battery voltage in the diesel exhaust fluid dosing valve
-Short to battery voltage in the diesel exhaust fluid controller harness
-Malfunctioning diesel exhaust fluid controller.

Cummins ISB4.5 CM2150 Fault Code: 3564 PID: SPN: 5491 FMI: 5 Aftertreatment Diesel Exhaust Fluid Line Heater Relay – Current Below Normal or Open Circuit.

Cummins ISB4.5 CM2150 Fault Code: 3563 PID: SPN: 5491 FMI: 4 Aftertreatment Diesel Exhaust Fluid Line Heater Relay – Voltage Below Normal or Shorted to Low Source.

Cummins ISB4.5 CM2150 Fault Code: 3562 PID: SPN: 5491 FMI: 3 Aftertreatment Diesel Exhaust Fluid Line Heater Relay – Voltage Above Normal or Shorted to High Source.

Cummins ISB4.5 CM2150 Fault Code: 3561 PID: SPN: 3361 FMI: 5 Aftertreatment Diesel Exhaust Fluid Dosing Unit – Current Below Normal or Open Circuit.

Cummins ISB4.5 CM2150 Fault Code: 3559 PID: SPN: 3361 FMI: 4 Aftertreatment Diesel Exhaust Fluid Dosing Unit – Voltage Below Normal or Shorted to Low Source.

Cummins ISB4.5 CM2150 Fault Code: 3558 PID: SPN: 3361 FMI: 3 Aftertreatment Diesel Exhaust Fluid Dosing Unit – Voltage Above Normal or Shorted to High Source.

WARNING!