FixVault

Coolant Temperature Sensor

  1. Turn off ignition. Remove panel from lower left of dash board. Disconnect wiring harness from ignition control unit (located above accelerator pedal). Remove cover from connector. Check that all pin connection sleeves are the same height.
    Fig 1: Ignition ECU Connector with Numbered Pins
    G62172Courtesy of VOLVO CARS OF NORTH AMERICA.
  2. Using an ohmmeter, measure resistance between pin No. 2 of connector F (on left suspension tower), and ground. If reading is incorrect, repeat measurement directly at the sensor. See COOLANT TEMPERATURE SENSOR RESISTANCE  table. Replace as applicable.
COOLANT TEMPERATURE SENSOR RESISTANCE

Resistance (Ohms) Temperature °F (°C)
6000 32 (0)
5000 68 (20)
1300 104 (40)
600 140 (60)
325 176 (80)
190 212 (100)
120 248 (120)