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ECT Sensor (B11/4)

  1. Voltage -  Connect DVOM between ME-SFI control module connector "E" terminals No. 28 and 29 (socket box terminals No. 84 and 85). Turn ignition on. Voltage should correspond with temperature. See COOLANT TEMPERATURE SENSOR VOLTAGE  table. If voltage is okay, test is complete. If voltage is not okay, perform remaining step. Possible causes are defective ME-SFI control module.
    COOLANT TEMPERATURE SENSOR VOLTAGE

    Temperature (1) Volts
    68°F (20°C) 3.4
    86°F (30°C) 2.9
    104°F (40°C) 2.4
    122°F (50°C) 1.9
    140°F (60°C) 1.5
    158°F (70°C) 1.2
    176°F (80°C) 0.9
    194°F (90°C) 0.7
    212°F (100°C) 0.5
    (1) Voltage values can vary plus or minus 5 percent.
  2. Resistance (Measured At ME-SFI Control Module) -  Turn ignition off. Connect DVOM between ME-SFI control module connector "E" terminals No. 28 and 29 (socket box terminals No. 84 and 85). Resistance should correspond with temperature. See COOLANT TEMPERATURE SENSOR RESISTANCE  table. If resistance is okay, test is complete. If resistance is not okay, possible causes are wiring harness failure or defective coolant temperature sensor (B11/4). Repair as necessary.
    COOLANT TEMPERATURE SENSOR RESISTANCE

    Temperature (1) Ohms
    68°F (20°C) 3090
    86°F (30°C) 2000
    104°F (40°C) 1330
    122°F (50°C) 900
    140°F (60°C) 630
    158°F (70°C) 440
    176°F (80°C) 320
    194°F (90°C) 230
    212°F (100°C) 170
    (1) Resistance values can vary plus or minus 5 percent.
  3. Resistance (Measured At Coolant Temperature Sensor) -  Turn ignition off. Disconnect coolant temperature sensor connector. Connect DVOM between coolant temperature sensor terminals. Resistance should correspond with temperature. See COOLANT TEMPERATURE SENSOR RESISTANCE  table. If resistance is okay, test is complete. If resistance is not okay, possible causes are defective coolant temperature sensor (B11/4). Repair as necessary.
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