Checking For Open-Circuits

Fig 1: Identifying Ignition ON

Courtesy of VOLVO CARS OF NORTH AMERICA.

Ring break diagnostic 

A ring break diagnostic should be run to determine whether the fault has occurred.

To carry out a full ring break diagnostic of the MOST system, proceed as follows:

1. Switch off the ignition and remove the key
2. Remove the fuse for the AM/FM tuner module (AFM) and the traffic message channel module (TMC)
3. Wait at least 3 minutes
4. Ignition on
5. Reinstall the fuse for the AM/FM tuner module (AFM) and the traffic message channel module (TMC) within 25 seconds
6. Wait at least 30 seconds after switching on the ignition before reading off the position of the open-circuit.

• Continue 

  See: READING OFF THE POSITION OF THE OPEN-CIRCUIT