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Pump Motor Relay

  1. With ECU connector still unplugged, turn ignition switch to the "ON" position. Jumper terminal No. 28 of ECU connector to ground.
    NOTE: Relay should not remain grounded for more than 2 seconds or damage to relay may occur.
  2. Hydraulic modulator should operate while jumper is installed. If hydraulic modulator does not function, check wiring from ECU connector to modulator. If wiring is not at fault, substitute a good relay and retest.
Fig 1: Volvo ABS Hydraulic Modulator Assembly
G58303Courtesy of VOLVO CARS OF NORTH AMERICA.