Scania EEC DTC 4121 Exhaust gas temperature sensor upstream of the particulate filter

EEC Exhaust Emission Control · Scania

Code 4121 (decimal). Some diagnostic tools show it in hexadecimal as 1019.

In short

The exhaust gas temperature sensor upstream of the particulate filter indicates incorrect values.

Applies to: EEC3

What does Scania EEC fault code 4121 mean?

What causes Scania DTC 4121?

How does the system react?

How to fix Scania EEC fault code 4121?

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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.

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