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Manifold Air Temperature (Mat) Sensor Test

  1. Disconnect the MAT wire harness connector from the MAT sensor. See Fig 1 *.
    Fig 1: Location of Manifold Air Temperature (MAT) Sensor
    G50I04605Courtesy of CHRYSLER MOTORS.
  2. Using a high input impedance (digital) volt-ohmmeter, test the resistance of the sensor. Resistance should be less than l000 ohms with a warm engine. Refer to the MANIFOLD AIR/FUEL TEMPERATURE (MAT) SENSOR RESISTANCE VALUES  table below.
    MANIFOLD AIR/FUEL TEMPERATURE (MAT) SENSOR RESISTANCE VALUES

    Degrees F° Degrees C° Resistance (Ohms)
    -40 -40 100,700
    0 -18 25,000
    20 -7 13,500
    40 4 7,500
    70 20 3,400
    100 38 1,600
    160 70 450
    212 100 185
  3. If any resistance is not within the range as specified in the table, replace the MAT sensor.
  4. Test the resistance of the wire harness between the ECU wire harness connector terminal "D-3" and the sensor connector terminal "C-8".
  5. Repair as necessary any circuits displaying a value greater than one ohm.