Scania EMS DTC 42249 SCR – Reductant pressure

EMS Engine Management System · Scania

Code 42249 (decimal). Some diagnostic tools show it in hexadecimal as A509.

In short

The pressure in the SCR system is reduced more than it should be in the periods when reductant is not injected.

Applies to: EMS S6

What does Scania EMS fault code 42249 mean?

What causes Scania DTC 42249?

How does the system react?

How to fix Scania EMS fault code 42249?

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This information is for guidance only. Always follow the manufacturer workshop manual and safety procedures; if in doubt, contact an authorised workshop.