Scania COO DTC 691 Communication with the ACS control unit

COO Coordinator · Scania · 6 variants

Code 691 (decimal). Some diagnostic tools show it in hexadecimal as 02B3.

In short

The communication between the coordinator and the ACS control unit has been interrupted.

Variant 1

Applies to: COO10 (COO)

What does Scania COO fault code 691 mean?

What causes Scania DTC 691?

How does the system react?

How to fix Scania COO fault code 691?

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Variant 2: Communication with the ACS control unit, communication error

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 691 in other Scania systems

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