Scania COO DTC 549 Manual activation of retarder

COO Coordinator · Scania · 6 variants

Code 549 (decimal). Some diagnostic tools show it in hexadecimal as 0225.

In short

The voltage in the circuit for the retarder lever or for the auxiliary brake lever has been above the permitted level.

Variant 1

Applies to: COO10 (COO)

What does Scania COO fault code 549 mean?

What causes Scania DTC 549?

What are the symptoms?

How to fix Scania COO fault code 549?

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Variant 2: Manual activation of retarder, too high a voltage

Applies to: COO11 (COO)

Variant 3

Applies to: COO8 (COO)

Variant 4

Applies to: COO9 (COO)

Variant 5

Applies to: COO7

Variant 6

Applies to: COO8

This information is for guidance only. Always follow the manufacturer workshop manual and safety procedures; if in doubt, contact an authorised workshop.

Code 549 in other Scania systems

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