Reductant circuit
Carry out the test "Checking SCR system heating" using SDP3 under EEC3>Inspection>Troubleshooting>Individual inspections. The test checks both the cooling system and electric heaters in the SCR system. When the fault has been found and rectified, start the engine. When the reductant doser and reductant tank temperature is high enough, start the SCR system and deactivate the fault code.
What you'll see
No driver-visible symptom recorded.
System reaction
No system-reaction text recorded.
Diagnostic depth
The reductant in the reductant circuit heats up too slowly.
Possible causes: The valve in the reductant tank heating system cannot be opened. Fault in the electric reductant heater in the reductant doser. Blockage in the coolant hoses from the engine to the SCR system. Blockage in the coolant pipes in the reductant pick-up unit. Fault in the electric reductant heater in the hose between the reductant pump and reductant doser. Fault in the electric reductant heater in the reductant return hose. Fault in the temperature sensor in the reductant pick-up unit or reductant doser. The engine coolant temperature is too low because there is a fault in the engine cooling system.