Scania COO DTC 779 Forward looking camera (FLC)

COO Coordinator · Scania · 5 variants

Code 779 (decimal). Some diagnostic tools show it in hexadecimal as 030B.

In short

CAN communication with forward looking camera (FLC) is interrupted.

Variant 1

Applies to: COO10 (COO)

What does Scania COO fault code 779 mean?

CAN communication with forward looking camera (FLC) is interrupted.

What causes Scania DTC 779?

- Short circuit in the cable harness for the voltage supply to the forward looking camera. - Open circuit in the cable harness for the voltage supply to the forward looking camera. - Internal fault in the forward looking camera. - Break in the circuit for the CAN bus.

How does the system react?

Yellow warning indication for degradation of advanced emergency braking (AEB) is displayed. Yellow warning indication for a lane departure warning fault is displayed.

What are the symptoms?

- The lane departure warning is inoperative. - Advanced emergency braking has impaired functionality. - The cruise control has impaired functionality.

How to fix Scania COO fault code 779?

  1. Check the fault codes in the forward looking camera.
  2. If the fault codes cannot be read:
  3. Check the CAN connection for the forward looking camera.
  4. Check the voltage supply to the forward looking camera
  5. Disconnect the battery.
  6. Measure the resistance between the coordinator pin on the internal CAN bus for CAN high (pin C9) and CAN low (pin C18).
  7. The resistance should be approx.
  8. 60 ohms.
  9. (Due to the two termination resistors connected in parallel.)
  10. Disconnect the battery.
  11. Measure the resistance between the coordinator pin on the internal CAN bus for CAN-high and voltage supply.
  12. The resistance should be in the order of a Megaohm.
  13. Disconnect the battery.
  14. Measure the resistance between the coordinator pin on the internal CAN bus for CAN-low and earth.
  15. The resistance should be in the order of a Megaohm.
  16. Disconnect one ECU unit from the internal CAN bus at a time to see if the fault disappears.

Variant 2: Front-facing camera (FLC), communication error

Applies to: COO11 (COO)

Detection

CAN communication with forward looking camera (FLC) is interrupted.

Possible cause

- Short circuit in the cable harness for the voltage supply to the forward looking camera. - Open circuit in the cable harness for the voltage supply to the forward looking camera. - Internal fault in the forward looking camera. - Break in the circuit for the CAN bus.

Symptoms

- The lane departure warning is inoperative. - Advanced emergency braking has impaired functionality. - The cruise control has impaired functionality.

How to fix

  1. Check the fault codes for the FLC control unit.
  2. Check the cable harness for CAN communication to the FLC control unit.
  3. Check the circuit of the FLC control unit supply voltage (30 voltage).
  4. Check the circuit of the FLC control unit activation signal (15 voltage).
  5. Check the cable harness and harness-to-component connector for the FLC control unit.
  6. Disconnect the power battery.
  7. Keep it disconnected during resistance measurements.
  8. Perform resistance measurement:
  9. Measure the resistance between the CAN bus for driver assisttance CAN-high (pin C9) and CAN-low (pin C18) on the coordinator.
  10. The resistance should be approx.
  11. 60 ohms.
  12. (Due to 120 ohm termination resistance at each end of the CAN bus).
  13. Measure the resistance between the CAN bus for driver assistance CAN-high (pin C9) and the voltage supply.
  14. The resistance should be in the order of a Megaohm.
  15. Measure the resistance between the CAN bus for driver assistance CAN-high (pin C9) and earth.
  16. The resistance should be in the order of a Megaohm.
  17. Measure the resistance between the CAN bus for driver assistance CAN-low (pin C18) and the voltage supply.
  18. The resistance should be in the order of a Megaohm.
  19. Measure the resistance between the CAN bus for driver assistance CAN-low (pin C18) and earth.
  20. The resistance should be in the order of a Megaohm.
  21. Check all control units on CAN bus for driver assistance.
  22. Check the harness-to-component connector, pin and cable harness.
  23. Check the harness-to-component connectors for all control units.
  24. Check if there is scarring or damaged, shorted or not connected pins.
  25. Disconnect one control unit at a time to see whether the fault disappears.

Variant 3

Applies to: COO8 (COO)

Detection

CAN communication with the forward looking camera (FLC) is interrupted.

Possible cause

- Short circuit in the cable harness for the voltage supply to the forward looking camera. - Open circuit in the cable harness for the voltage supply to the forward looking camera. - Internal fault in the forward looking camera. - Break in the circuit for the CAN bus.

Symptoms

- The lane departure warning is inoperative. - Advanced emergency braking has impaired functionality. - The cruise control has impaired functionality.

How to fix

  1. Check the fault codes in the forward looking camera.
  2. If the fault codes cannot be read:
  3. Check the CAN connection for the forward looking camera.
  4. Check the voltage supply to the forward looking camera
  5. Disconnect the battery.
  6. Measure the resistance between the coordinator pin on the internal CAN bus for CAN-high (pin B5) and CAN-low (pin B14).
  7. The resistance should be approx.
  8. 60 ohms.
  9. (Due to the two termination resistors connected in parallel.)
  10. Disconnect the battery.
  11. Measure the resistance between the coordinator pin on the internal CAN bus for CAN-high and voltage supply.
  12. The resistance should be in the order of a Megaohm.
  13. Disconnect the battery.
  14. Measure the resistance between the coordinator pin on the internal CAN bus for CAN-low and earth.
  15. The resistance should be in the order of a Megaohm.
  16. Disconnect one ECU unit from the internal CAN bus at a time to see if the fault disappears.

Variant 4: Communication with the FLC control unit

Applies to: COO7

Detection

Communication between the coordinator and the FLC control unit has been interrupted.

Possible cause

The fault may be due to: - Short circuit or open circuit in the FLC control unit supply voltage circuit. - Internal fault in the FLC control unit. - Open circuit in the CAN bus circuit.

System reaction

Lane departure warning and emergency brake functions are not working.

How to fix

  1. Check whether the FLC control unit has generated any fault codes.
  2. If not: Check the CAN bus connection to the FLC control unit.
  3. Check the FLC control unit supply voltage circuit (30) and the FLC control unit activation signal circuit (15).
  4. Check the cable harness and harness-to-component connectors for the sub data bus.
  5. Measure the resistance between coordinator pins C18 and C9 with the battery disconnected.
  6. Resistance should be around 60 ohms.
  7. (Due to the two termination resistors connected in parallel.) If all control units connected to the sub data bus generate fault codes regarding communication faults:
  8. Measure the resistance between coordinator pin C18 and voltage with the battery disconnected.
  9. Resistance should be in the order of Megaohms.
  10. Measure the resistance between coordinator pin C9 and earth with the battery disconnected.
  11. Resistance should be in the order of Megaohms.
  12. Disconnect one control unit at a time to see whether the fault disappears.

Variant 5: Forward looking camera

Applies to: COO8

Detection

CAN communication with the forward looking camera (FLC) is interrupted.

Possible cause

The fault may be due to: - Short circuit or open circuit in the supply voltage circuit for the forward looking camera. - Internal fault in the forward looking camera. - Open circuit in the CAN bus circuit.

System reaction

- The lane departure warning is inoperative. - Advanced emergency braking has impaired functionality. A warning on fault with lane departure warning and advanced emergency braking is displayed on the instrument cluster.

How to fix

  1. Check the fault codes in the forward looking camera.
  2. If the fault codes cannot be read:
  3. Check the CAN connection for the forward looking camera.
  4. Check the supply voltage to the forward looking camera.
  5. Measure the resistance between the coordinator pin for CAN high (pin B5) and CAN low (pin B14) of the internal CAN bus with the battery disconnected.
  6. Resistance should be around 60 ohms.
  7. (Due to the two termination resistors connected in parallel.)
  8. Measure the resistance between the coordinator pin for CAN high of the internal CAN bus and voltage with the battery disconnected.
  9. Resistance should be in the order of Megaohms.
  10. Measure the resistance between the coordinator pin for CAN low of the internal CAN bus and earth with the battery disconnected.
  11. Resistance should be in the order of Megaohms.
  12. Disconnect one ECU unit from the internal CAN bus at a time to see if the fault disappears.

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

Code 779 in other Scania systems

Compare code 779 in every system →