Scania EMS DTC 4120 SCR control unit

EMS Engine Management System · Scania · 2 variants

Code 4120 (decimal). Some diagnostic tools show it in hexadecimal as 1018.

In short

Shorted to ground or damaged, from the sensor diagnostics

Variant 1: Resistance below normal or shorted to ground

Applies to: EMS10

What does Scania EMS fault code 4120 mean?

What causes Scania DTC 4120?

What are the symptoms?

How to fix Scania EMS fault code 4120?

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Variant 2

Applies to: EMS S6

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

Code 4120 in other Scania systems

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