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Home >> Volvo >> 1991 >> 240 SE, AW70L >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Ignition System >> Timing Control Systems >> Detonation (Knock) Sensor
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Detonation (Knock) Sensor

  1. Disconnect knock sensor connector. Connect jumper wire across knock sensor terminals No. 1 and 2. See Fig 1 . Turn ignition off. Disconnect ignition ECU connector.
    Fig 1: Identifying Knock Sensor Connector Terminals
    G121550Courtesy of VOLVO CARS OF NORTH AMERICA.
  2. Remove cover from ECU connector to expose pin identification numbers. Connect ohmmeter leads between pins No. 12 and 13 of ignition ECU connector. See Figure . Ohmmeter should indicate zero ohms.
  3. If ohmmeter resistance is high (infinity), one or both wires may be shorted. Remove jumper wire, and take reading with ohmmeter on each wire. Replace damaged wires as required. If wires are not damaged, replace knock sensor.