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Power Circuit Checks

  1. On all models except 760 GLE, connect a voltmeter between ground and ECU connector pin No. 5 and then to pin No. 6. See Fig 1 .
  2. On 760 GLE, connect voltmeter to ECU connector pin No. 8 (Yellow wire) and ground.
  3. On all Models, turn ignition switch to the "ON" position. Voltmeter should read 11-12 volts (depending on battery voltage).
  4. On all models except 760 GLE, if voltage is not present, check wire from ECU connector to in-line fuse located on left shock tower.
  5. On all models, if no voltage or low voltage is indicated, check for an open between ignition ECU and fuel ECU unit, or there may be a problem with fuel ECU.
Fig 1: Electronic Control Unit (Ignition) Terminal Identification
G121548Courtesy of VOLVO CARS OF NORTH AMERICA.


  1. Using a voltmeter, connect voltmeter leads between ECU connector pin No. 6 (Blue wire) and ground. See Figure . Turn ignition switch to the "ON" position.
  2. Voltmeter should read 12 volts. If no voltage is indicated, check wiring. See WIRING DIAGRAMS article.