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EGR Valve Lift Sensor

  1. Connect System Checker harness between ECU and connector. Turn ignition ON, and measure voltage between connector "C" terminals No. 13 (Yellow/White) and No. 12 (Green/White). If voltage is 4.75-5.25 volts, go to next step. If voltage is not within specification, substitute a known-good ECU and re-check.
  2. Measure voltage between connector "C" terminals No. 8 (Red/Blue) and No. 12 (Green/White). Voltage should be 1.0-1.4 volts. If voltage is not within specification , go to next step. If voltage is within specification, substitute a known-good ECU and re-test EGR components. See SYSTEM TESTING  . If EGR still does not operate properly, replace the original ECU.
  3. Turn ignition switch OFF. Check for open or short circuit in Yellow/White, Yellow and Green/White wires between EGR valve lift sensor and ECU.
    NOTE: If there is no voltage, or if the voltage is low, check for a shorted wire. If voltage is high, there may an open in the wire or a bad connection.

    If there is any abnormality, go to next step. If not, the wires are faulty.

  4. Turn ignition switch ON. Remove the #16 vacuum hose from the EGR valve, then connect a vacuum pump to upper hose of EGR valve. While applying vacuum, measure the voltage between connector "C" terminals No. 8 (Red/Blue) and No. 12 (Green/White). If the voltages gradually rises, go to next step. If the voltage does not gradually rise, the EGR valve lift sensor is faulty.
  5. Substitute a known-good ECU and re-test EGR components. See SYSTEM TESTING  . If EGR now operates properly, replace the original ECU.
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