Checking ground terminal

Fig 1: Identifying Ignition OFF

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 2: Disconnecting Control Unit

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• Ignition off.
• Main unit disconnected.
• Switch off all equipment that takes power from the battery (courtesy lighting, radio etc).

  For the keypad/car phone module  connect an ohmmeter between the battery negative terminal and #8 on the breakout box.

  For the car phone box  connect an ohmmeter between the battery negative terminal and #30 on the breakout box.

  Fig 3: Breakout Box

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

  Courtesy of VOLVO CARS OF NORTH AMERICA.

The ohmmeter should read approximately 0 Ω. 

• OK 

  OKAY:  Troubleshooting has been completed.

• NOT OK 

  Refer to Checking for open-circuits, contact resistance and oxidation