Scania ACS DTC 521 Orange CAN bus

ACS Articulation Control System · Scania

Code 521 (decimal). Some diagnostic tools show it in hexadecimal as 0209.

In short

Open circuit in communication on the orange CAN bus.

Applies to: ACS6 (ACS)

What does Scania ACS fault code 521 mean?

Open circuit in communication on the orange CAN bus.

What causes Scania DTC 521?

- Fault in the ACS control unit connection to the orange CAN bus. - Fault on the orange CAN bus. - Wake-up signal to the ACS control unit is short-circuited to voltage supply. - Short circuit between CAN high and voltage supply. - Overloading on orange CAN bus. - Fault in another control unit on orange CAN bus.

How to fix Scania ACS fault code 521?

  1. Check fault codes in other control units on the orange CAN bus.
  2. Check the ACS control unit connection to the orange CAN bus.
  3. Check the orange CAN bus:
  4. Disconnect the battery and measure the resistance between CAN high and CAN low on the ACS control unit.
  5. Resistance should be close to 60 ohm.
  6. Disconnect the battery and measure the resistance between CAN high on the ACS control unit and CAN high on another control unit on the orange CAN bus.
  7. Resistance should be close to 0 ohm.
  8. Disconnect the battery and measure the resistance between CAN low on the ACS control unit and CAN low on another control unit on the orange CAN bus.
  9. Resistance should be close to 0 ohm.
  10. Check the wake-up signal to the ACS control unit (15 voltage).

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

Code 521 in other Scania systems

Compare code 521 in every system →