Scania CMS DTC 640 Hydraulic flow in primary steering circuit

CMS CMS control unit · Scania

Code 640 (decimal). Some diagnostic tools show it in hexadecimal as 0280.

In short

The dual-circuit steering position sensor for circuit 1 (T55), connected to pins B19 and B21 on the control unit, indicates that the flow is too low.

Applies to: CMS1 (CMS)

What does Scania CMS fault code 640 mean?

What causes Scania DTC 640?

What are the symptoms?

How to fix Scania CMS fault code 640?

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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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