Scania EMS DTC 6521 Secondary brake pressure circuit pressure signal, below normal.

EMS Engine Management System · Scania

Code 6521 (decimal). Some diagnostic tools show it in hexadecimal as 001979.

In short

The circuit pressure is constantly below the required level for operating the pneumatic actuators on the engine for an extended period of time.

Applies to: EMS10

What does Scania EMS fault code 6521 mean?

What causes Scania DTC 6521?

What are the symptoms?

How to fix Scania EMS fault code 6521?

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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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