Checking The Cable And Component
Checking the fault cause
Check the fault cause as follows:
- Ignition off.
- Disconnect the MOST connector from the subwoofer module (SUB).
- Connect the MOST cable to special tool: see 9512867
- Ignition on.
- Activate the infotainment unit.
- Check that the communication on the MOST-net works by reading out the status for the parameter MOST locked for at least 30 seconds. The parameter indicates whether the MOST network is closed and communication possible. Click on the VCT2000 symbol to obtain a MOST network status reading.
- If the parameter shows that the MOST network is not closed, check the receiving control module in the same way as described above.
The communication on the MOST network is working if the menu text is displayed. If this is the case, the fault cause is in the subwoofer module (SUB). Continue the fault-tracing by checking the component.
The communication on the MOST network is not working if the menu text is not displayed. The fault cause is then in the MOST cable for the next control module. Continue the fault-tracing by checking the fiber optic cable.
Checking the cable
- Check the MOST connection. Check for dirt, loose connections and damage.
- Replace the MOST cable if no fault is found in the MOST terminal.
Checking the component
- Check the audio module (AUD) power supply and ground connection for the Accessory USB unit (AUU).
- Check the MOST connection. Check for dirt, loose connections and damage.
- If no fault is found, replace the Accessory USB unit (AUU).
Remedy as necessary.
Other information
- see SUBWOOFER MODULE (SUB), REPLACING
- see CHECKING THE VOLTAGE / GROUND TERMINAL
- see SIGNAL SPECIFICATION
- see FIBER OPTIC CABLE HARNESS, REPAIRING
- see OPTICAL WIRING HARNESS CHECK
- see LOCATION OF COMPONENTS
- Continue
Refer to VERIFICATION
Checking the fault cause
Check the fault cause as follows:
- Ignition off.
- Unplug the MOST-connector from Accessory USB unit (AUU).
- Connect the MOST cable to special tool: see 9512867
- Ignition on.
- Activate the infotainment system.
- Check that the communication on the MOST-net works by reading out the status for the parameter MOST locked for at least 30 seconds. The parameter indicates whether the MOST network is closed and communication possible. Click on the VCT2000 symbol to obtain a MOST network status reading.
- If the parameter shows that the MOST network is not closed, check the receiving control module in the same way as described above.
The communication on the MOST network is working if the menu text is displayed. The cause of the fault is in the Accessory USB unit (AUU). Continue the fault-tracing by checking the component.
The communication on the MOST network is not working if the menu text is not displayed. The fault cause is then in the MOST cable for the next control module. Continue the fault-tracing by checking the fiber optic cable.
Checking the cable
- Check the MOST connection. Check for dirt, loose connections and damage.
- Replace the MOST cable if no fault is found in the MOST terminal.
Checking the component
- Check the audio module (AUD) power supply and ground connection for the Accessory USB unit (AUU).
- Check the MOST connection. Check for dirt, loose connections and damage.
- If no fault is found, replace the Accessory USB unit (AUU).
Remedy as necessary.
Other information
- see UNIVERSAL BUS MODULE (USB)
- see CHECKING THE SUPPLY VOLTAGE/GROUND TERMINAL
- see SIGNAL SPECIFICATION
- see FIBER OPTIC CABLE HARNESS, REPAIRING
- see OPTICAL WIRING HARNESS CHECK
- see LOCATION OF COMPONENTS
- Continue
Refer to VERIFICATION