Checking the cable between the selector switch and the brake valve

Fig 1: Identifying Ignition OFF

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 2: Disconnecting Connector

Courtesy of VOLVO CARS OF NORTH AMERICA.

• Ignition off.
• Brake valve disconnected.
• Disconnect the selector switch.

  Connect an ohmmeter between selector switch connector terminal #2 and the brake valve connector (terminal #1).

  Fig 3: Identifying Selector Switch 5-Pin Connector And Brake Valve 2-Pin Connector

  Courtesy of VOLVO CARS OF NORTH AMERICA.
  Fig 4: Identifying Ohmmeter

  Courtesy of VOLVO CARS OF NORTH AMERICA.

The ohmmeter should read 0 Ω. 

• OK 

  Refer to Checking brake valves 

• NOT OK 

  Refer to Checking for an open-circuit