Checking ground point

Fig 1: Identifying Ignition OFF

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 2: Disconnecting Control Unit

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• Ignition off.
• Control unit disconnected.
• Switch off all battery loads such as entrance lights and radio.

  Connect an ohmmeter between the battery negative terminal and #3 on the test box.

  Fig 3: Breakout Box

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

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The ohmmeter should display approximately 0 (. 

• OK 

  Refer to Checking the power supply 

• NOT OK 

  Refer to Checking for open circuits, contact resistance and oxidation