Scania MBS DTC 522 #Not implemented. Electrical error on CAN bus 2

MBS MBS control unit · Scania

Code 522 (decimal). Some diagnostic tools show it in hexadecimal as 020A.

In short

The CAN-controller of CAN bus 2 has entered state bus-off, which indicates a communication error. There is a short circuit on CAN bus 2.

Applies to: MBS3 (MBS)

What does Scania MBS fault code 522 mean?

The CAN-controller of CAN bus 2 has entered state bus-off, which indicates a communication error. There is a short circuit on CAN bus 2.

What causes Scania DTC 522?

• Defect wiring of CAN bus 2: - short circuit between CAN-high and CAN low. - short circuit between CAN-high and supply voltage. - short circuit between CAN-high and ground. - short circuit between CAN-low and supply voltage. - short circuit between CAN-low and ground. • Defect ECU unit(s) on the CAN bus 2.

How does the system react?

Functions dependent on information from CAN bus 2 are degraded, meaning components connected to MBS expansion node A, B, C and D.

What are the symptoms?

Functionality connected to MBS expansion nodes A, B, C and D may not work as intended.

How to fix Scania MBS fault code 522?

  1. Check wiring for CAN bus 2:
  2. Measure the resistance (with the battery disconnected) between CAN-high and CAN-low.
  3. It should be close to 60 ohm (one 120 ohm termination resistor in each end of the CAN-bus).
  4. Measure the resistance (with the battery disconnected) between CAN-high on MBS and CAN-high on any other unit (e.g.
  5. MBS) on CAN bus 2.
  6. It should be close to zero ohm.
  7. Measure the resistance (with the battery disconnected) between CAN-low on MBS(Master) and CAN-low on any other unit on CAN bus 2.
  8. It should be close to zero ohm.
  9. Trouble shoot CAN bus cable harness and connectors

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

Code 522 in other Scania systems

Compare code 522 in every system →