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Home >> Mazda >> 1998 >> 626 DX, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - Testing >> Diagnostic Trouble Codes >> DTC P0107: EGR Boost Sensor >> Condition
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DTC P0107: EGR Boost Sensor: Condition

This DTC indicates EGR boost pressure sensor circuit input signal is less than the self-test minimum. Possible causes for this fault are:

  1. Check EGR Boost Sensor VREF Voltage

    Turn ignition off. Disconnect EGR boost sensor. Turn ignition on. Measure voltage between SIG RTN terminal and VREF terminal at EGR boost sensor wiring harness connector. If voltage is 4-6 volts, go to next step. If voltage is not 4-6 volts, repair open VREF circuit.
  2. Check EGR Boost Circuit Resistance

    Leave EGR boost sensor disconnected. Turn ignition off. Disconnect PCM 104-pin connector. Inspect for damaged pins and repair if necessary. Connect Breakout Box (014-00950), leaving PCM disconnected. Measure resistance between test pin No. 34 (EGR Boost) and EGR boost terminal at EGR boost sensor wiring harness connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in EGR boost circuit and repeat QUICK TEST. See TESTS W/CODES - INTRODUCTION article.
  3. Check EGR Boost Circuit For Short To Ground

    Leave ignition off and EGR boost sensor disconnected. Measure resistance between test pin No. 34 (EGR Boost) and test pins No. 91 (SIG RTN), 51 and 103 (PWR GND) at breakout box. If each measurement is 10 k/ohms or more, go to next step. If any measurement is less than 10 k/ohms, repair short in EGR boost circuit and repeat QUICK TEST. See TESTS W/CODES - INTRODUCTION article.
  4. Check EGR Boost Sensor Response

    Leave ignition off. Disconnect vacuum hose between EGR boost sensor and EGR boost solenoid. Inspect hose for damage and repair if necessary. Connect vacuum pump to EGR boost sensor vacuum port. Turn ignition on. While measuring voltage between test pins No. 34 (EGR boost) and 51 (PWR GND), slowly apply 21 in. Hg. If voltage response is 0.8-1.5 volts, go to next step. If voltage is not as specified, replace EGR boost sensor and repeat QUICK TEST. See TESTS W/CODES - INTRODUCTION article.