Grand Cherokee
NOTE:
For circuit identification and wiring diagram, see WIRING DIAGRAMS article. After each repair procedure has been completed, reconnect all components. Perform TEST VER-5
under VERIFICATION TESTS to ensure system is functioning properly.
- Turn ignition on, engine off. Using scan tool, read and record INTAKE AIR TEMP DEG value. Remove IAT sensor. See Fig 1 or Fig 2 . Using a thermometer, read temperature inside IAT sensor opening. If IAT sensor value is within 10 degrees of thermometer reading, reinstall IAT sensor. Reconnect IAT sensor connector and go to next step. If IAT sensor value is not within 10 degrees of thermometer reading, replace IAT sensor.
- Turn ignition off. Visually inspect related connectors and wiring harness for damage. Repair connectors and wiring harness as necessary. If connectors and wiring harness are okay, reconnect all connectors. Start engine. Wiggle ECT sensor connector and wiring harness while monitoring scan tool display. If GOOD TRIP counter display count changes to "0", repair connector or wiring harness where wiggling caused display to change. If GOOD TRIP counter display count does not change to "0", no problem is indicated at this time. Test is complete. Check for any related technical service bulletins that may apply.