1997 Cadillac Eldorado BaseFACTORY OEM SERVICE PROCEDURE

Engine Coolant Temperature (ECT) Sensor

If a coolant sensor-related diagnostic trouble code is present, see the TESTS W/CODES article. An out-of-calibration sensor may not set a diagnostic trouble code. Use following procedure to test sensor calibration. Disconnect ECT sensor connector. Measure resistance between sensor terminals. Resistance should be high when engine is cold and drop as engine warms. See ECT SENSOR RESISTANCE VALUESΒ  table.

ECT SENSOR RESISTANCE VALUES (1)

F (Β°C) Ohms
212 (100) 177
194 (90) 241
158 (70) 467
104 (40) 1459
68 (20) 3520
23 (-5) 12,300
14 (-10) 16,180
0 (-18) 25,000
-4 (-20) 28,680
-22 (-30) 52,700
-40 (-40) 100,700
(1) Measure resistance across sensor terminals.
Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.

Rather have a pro handle this?

A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.

Comes to youSame-day available12-month warranty
Get a Free Quote

No obligation. See pricing before you book.