Checking Cable And Component

If the result of the ring break diagnostic is POOR, the infotainment control module (ICM) is receiving a signal on the MOST network. However it is unable to decode the signals because the luminance of the signals is too weak or the signals are distorted.

If the result from the ring break diagnostic is OK, the fault is intermittent.

Fault-tracing using the ring break diagnostic assumes that the fault is permanent or active when the test is run, i. e. the system is powered having been off.

HINT: If diagnostic trouble code (DTC) ICM-DC01 is intermittent, read off the status of the ring break diagnostic from the frozen values in Vehicle communication. 

HINT: Note that the AM/FM tuner module (AFM) and the traffic message channel module (TMC) are not normally included in a ring break diagnostic if the fuse is not removed. This means that the position of the open-circuit moves two steps backwards in the MOST network. 

HINT: On fully equipped vehicles, if the open-circuit position is 5, this may be because of: 

• Multimedia module (MMM)
• The fiber optic cable between the multimedia module (MMM) and the AM/FM tuner module (AFM)
• AM/FM tuner module (AFM)
• The fiber optic cable between the AM/FM tuner module (AFM) and the traffic message channel module (TMC)
• Traffic message channel module (TMC)
• The fiber optic cable between the traffic message channel module (TMC) and the audio module (AUD).

Check the communication on the MOST network by bypassing the control modules one by one on the MOST network as follows:

• Ignition off
• Disconnect the MOST connector from the relevant control module
• Connect the MOST cable to special tool: 9512867
• Ignition on
• Activate the infotainment system
• Check that the communication on the MOST network is functioning by reading off the status of the MOST locked parameter for at least 30 seconds. The parameter indicates whether the MOST network is closed and communication possible.

If the communication on the MOST network is stable when a control module is disconnected, check the power supply and the ground terminal on the relevant control module. Check for intermittent faults. Try replacing the component if no fault is found.

Click the VCT2000 symbol to read off the status of the MOST network.

Fig 1: Identifying VCT2000 Diagnostic Tool Symbol In VIDA

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 2: View Of MOST Network

Courtesy of VOLVO CARS OF NORTH AMERICA.

• Continue 

  See: VERIFICATION 

Select the control module to be checked from the list.

1. Media player module (MPM).

See: CHECKING CABLES AND COMPONENTS, MEDIA PLAYER MODULE (MPM) 

2. Phone module (PHM)

See: CHECKING CABLES AND COMPONENTS, PHONE MODULE (PHM) 

3. Subwoofer module (SUB)

See: CHECKING CABLES AND COMPONENTS, SUBWOOFER MODULE (SUB) 

4. Global positioning system module (GPS)

See: CHECKING THE CABLE AND COMPONENT, GLOBAL POSITIONING SYSTEM MODULE (GPS) 

Select the control module to be checked from the list.

1. Audio module (AUD)

See: CHECKING CABLES AND COMPONENTS, AUDIO MODULE (AUD) 

2. Traffic message channel module (TMC)

See: CHECKING THE CABLE AND COMPONENT, TRAFFIC MESSAGE CHANNEL MODULE (TMC) 

3. AM/FM tuner module (AFM)

See: CHECKING CABLES AND COMPONENTS, AM/FM TUNER MODULE (AFM) 

4. Multimedia module (MMM)

See: CHECKING CABLES AND COMPONENTS, MULTIMEDIA MODULE (MMM) 

5. Infotainment control module (ICM)

See: CHECKING CABLES AND COMPONENTS, INFOTAINMENT CONTROL MODULE (ICM)