FixVault

Engine Coolant Temperature (ECT) Sensor

  1. Disconnect ECT sensor connector. Using DVOM, measure resistance between sensor terminals. If resistance is not as specified, replace sensor. See ECT SENSOR & IAT SENSOR RESISTANCE table. If resistance is as specified, go to next step.
  2. Check continuity of Tan/Black wire between ECT harness connector and terminal A16 at PCM connector. Also, check continuity of Black/Light Blue wire between ECT harness connector and terminal A4 at PCM connector.
  3. If continuity exists at both wires, no problem is indicated. If continuity does not exist at one or both wires, repair wiring as necessary.
ECT SENSOR & IAT SENSOR RESISTANCE

Temperature °F (°C) Minimum Ohms Maximum Ohms
-40 (-40) 291,490 381,710
-4 (-20) 85,850 108,390
14 (-10) 49,250 61,430
32 (0) 29,330 35,990
50 (10) 17,990 21,810
68 (20) 11,370 13,610
77 (25) 9120 10,880
86 (30) 7370 8750
104 (40) 4900 5750
122 (50) 3330 3880
140 (60) 2310 2670
158 (70) 1630 1870
176 (80) 1170 1340
194 (90) 860 970
212 (100) 640 720
230 (110) 480 540
248 (120) 370 410