Scania COO DTC 550 Manual activation of retarder lever

COO Coordinator · Scania · 6 variants

Code 550 (decimal). Some diagnostic tools show it in hexadecimal as 0226.

In short

The voltage in the circuit for the retarder lever or for the auxiliary brake lever has assumed an inadmissible value.

Variant 1: Manual activation of the retarder lever

Applies to: COO10 (COO)

What does Scania COO fault code 550 mean?

What causes Scania DTC 550?

What are the symptoms?

How to fix Scania COO fault code 550?

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Variant 2: Manual activation of the retarder lever, incorrect 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 550 in other Scania systems

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