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Code 31, 33 & 39

  1. Ensure ignition is off. Disconnect ABS control unit harness connector. See Figure . Using ohmmeter, check resistance between selected control unit harness connector terminals. See Figure . See CONTROL UNIT RESISTANCE CHART. Resistance should be 1 ohm or less. If resistance is within specification, go to next step. If resistance is not within specification, go to step 4).
    CONTROL UNIT RESISTANCE

    Trouble Code (1) Terminals
    21 21 & 23
    23 (4WD) 4 & 22
    23 (FWD) 4 & 5
    25 24 & 26
    27 8 & 9
    (1) Using ohmmeter, check resistance between specified terminals.
  2. Ensure ignition is off. Disconnect hydraulic unit valve relay. Hydraulic unit valve relay (5 terminal) is located on hydraulic unit. Ensure ABS control unit harness connector is disconnected. Turn ignition on. Using voltmeter, measure voltage between ABS control unit harness connector terminals No. 2, 18 and 35, and terminal No. 20. See Figure . Voltage should be 0 volts. If voltage is within specification, replace ABS control unit. If voltage is not within specification, go to next step.
  3. Ensure ignition is off. Disconnect hydraulic unit harness connector. Ensure ABS control unit harness connector is disconnected. Turn ignition on. Using voltmeter, measure voltage between ABS control unit harness connector terminals No. 2, 18 and 35, and terminal No. 20. See Figure . Voltage should be 0 volts. If voltage is within specification, replace hydraulic unit. If voltage is not within specification, inspect and repair circuit(s) between control unit and hydraulic unit.
  4. Turn ignition off. Ensure hydraulic unit valve relay and ABS control unit harness connectors are connected. Disconnect hydraulic unitharness connector. Using ohmmeter, check resistance between hydraulic unit terminals 1, 3 and 4, and terminal 11. See Figure .
    NOTE: Terminal view shown in Figure is of harness connector.
  5. Resistance should be 1 ohm or less. If resistance is within specification, inspect and repair circuit(s) between hydraulic unit and ABS control unit. If resistance is not within specification, replace hydraulic unit.
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