Applies to: EMD0EMD1
What does Scania EMD fault code 5504 mean?
Invalid signal from the NOx sensor.
What causes Scania DTC 5504?
- Open circuit in the circuit between the EMS control unit and the EEC control unit.
How does the system react?
- Produces torque reduction. - Reductant dosing is deactivated.
How to fix Scania EMD fault code 5504?
- Check the cable harness and harness-to-component connectors between the EMS control unit and the EEC control unit.
- Run Exhaust gas aftertreatment, troubleshooting the liquid components of the SCR system.
- If communication is not working, renew the EEC control unit.
- Verification Run Exhaust gas aftertreatment, function test SCR > Checking the NOx sensors.
- When the NOx sensor has warmed up, the fault code is deactivated.
This information is for guidance only. Always follow the manufacturer workshop manual and safety procedures; if in doubt, contact an authorised workshop.