IAT And ECT Sensor Wiring Diagram (PART 1)

Intake Air Temp (IAT) And Engine Coolant Temp (ECT) Sensor Wiring Diagram (1993, 1994, 1995 4.0L Jeep Grand Cherokee)

NOTE: The above intake air temperature (IAT) and engine coolant temperature (ECT) sensor wiring diagram applies only to 1993, 1994, 1995 4.0L Jeep Grand Cherokee.

IAT And ECT Sensor Wiring Diagram (PART 2)

Intake Air Temp (IAT) And Engine Coolant Temp (ECT) Sensor Wiring Diagram (1993, 1994, 1995 4.0L Jeep Grand Cherokee)

The intake air temperature (IAT) and engine coolant temperature (ECT) sensors share ground with several other sensors thru' the BLK/LT BLU wire.

PCM connector pin 4 is the source of the ground that's fed thru' the BLK/LT BLU wire.

IAT And ECT Sensor Connector Problem

Engine Coolant Temp (ECT) Sensor Wiring Diagram (1993, 1994, 1995 4.0L Jeep Grand Cherokee)

NOTE: The most common problem encountered with the ECT (and IAT) sensor is the insulation peeling off of the wires and shorting together. The above photo, of 1995 Jeep 4.0L Grand Cherokee, is an actual example of the ECT sensor harness connector having this exact problem.

Where To Buy The IAT and ECT Sensors And Save

The best place to comparison shop and get an idea of how much your Grand Cherokee's IAT and ECT sensors cost (and how much you can save) is here:

Not sure if the above IAT and ECT sensor fits your particular Jeep Grand Cherokee? Don't worry, once you get to the site, they'll make sure it fits by asking you the particulars of your vehicle. If it doesn't fit, they'll find you the right one.

More Jeep 4.0L Test Tutorials

If this tutorial was helpful/informative, you can find a complete list of tutorials here: Jeep 4.0L Index of Articles.

Here's a sample of the tutorials you'll find there:

  1. How To Test Trouble Code P0135 (1996-2000 Jeep 4.0L).
  2. How To Test The MAP Sensor (1997-2003 Jeep 4.0L).
  3. How To Do A Cylinder Balance Test (Jeep 4.0L).
  4. Jeep PWM Fan Relay Test Troubleshooting An Overheating Condition.
  5. How To Test The Crank Sensor (Jeep 4.0L -1997-2004).