Test TC-128A - Closed Loop Temperature Not Reached
NOTE:
For connector terminal ID, see CONNECTOR IDENTIFICATION DIRECTORY
. For wiring diagram, see WIRING DIAGRAMS - 2.4L
article.
- This test will be invalid if thermostat is stuck open. Diagnostic Trouble Code (DTC) may be stored in Powertrain Control Module (PCM) if engine temperature does not become greater than 50°F (10°C) within 13 minutes after engine is started. Possible causes are: defective thermostat or engine coolant temperature sensor, defective connector terminals or wiring, extremely cold ambient temperatures or defective PCM.
- Check that thermostat is operating correctly. If thermostat operates correctly, go to next step. If thermostat is not operating correctly, replace thermostat. Perform TEST VER-2A.
- Start and warm engine until engine coolant temperature is greater than 80°F (27°C). Shut engine off. Disconnect connector at engine coolant temperature sensor. Engine coolant temperature sensor is located near thermostat housing and contains Black/Light Blue and Tan/Black wires in the connector.
- Inspect connector for miswired or damaged terminals. If connector is miswired or terminals are damaged, repair as necessary. Perform TEST VER-2A. If connector is not miswired or terminals are not damaged, go to next step.
- Using external ohmmeter, measure resistance between terminals on engine coolant temperature sensor. If resistance is less than 11,000 ohms, go to next step. If resistance is 11,000 ohms or more, replace engine coolant temperature sensor. Perform TEST VER-2A.
- Turn ignition off. Disconnect connectors from PCM. The PCM is located between driver's side front fender and power distribution center, near battery.
- Inspect connectors for miswired or damaged terminals. If connectors are miswired or terminals are damaged, repair as necessary. Perform TEST VER-2A. If connectors are not miswired or terminals are not damaged, replace PCM. Perform TEST VER-2A.