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Manifold Air Temperature (MAT) Sensor Test

  1. Disconnect wire harness connector from MAT sensor. See Figure . Test resistance of sensor with a high impedance digital ohmmeter. Resistance should be less than 1000 ohms with engine warm. Replace sensor if resistance is not within range and temperature specified. See TEMPERATURE & RESISTANCE VALUES (CTS & MAT SENSOR)  table.
  2. Test resistance of wire harness between ECU wire harness connector terminal D-3 and sensor connector terminal. Repeat test with terminal C-8 at ECU and sensor connector terminal. Repair wire harness if an open circuit or resistance of greater than one ohm is indicated.
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