Scania EMU DTC 20521 Vehicle charging inlet box R130, negative contactor, stuck in closed position

EMU EMU control unit · Scania

Code 20521 (decimal). Some diagnostic tools show it in hexadecimal as 005029.

In short

The control unit indicates that the negative contactor cannot be opened.

Applies to: EMU1 (ECS)

What does Scania EMU fault code 20521 mean?

What causes Scania DTC 20521?

How does the system react?

How to fix Scania EMU fault code 20521?

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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.

Code 20521 in other Scania systems