Scania EST DTC 633 Switch for tag axle steering disengagement

EST EST control unit · Scania

Code 633 (decimal). Some diagnostic tools show it in hexadecimal as 0279.

In short

The tag axle steering disengagement switch has been activated for an implausible amount of time.

Applies to: EST1 (EST)

What does Scania EST fault code 633 mean?

What causes Scania DTC 633?

What are the symptoms?

How to fix Scania EST fault code 633?

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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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