Scania CMS DTC 771 Engine start switch signal

CMS CMS control unit · Scania

Code 771 (decimal). Some diagnostic tools show it in hexadecimal as 0303.

In short

Control unit pins B4 and B7 have been activated simultaneously.

Applies to: CMS1 (CMS)

What does Scania CMS fault code 771 mean?

What causes Scania DTC 771?

What are the symptoms?

How to fix Scania CMS fault code 771?

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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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