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Home >> Eagle >> 1997 >> Talon Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - Non-Turbo >> Trouble Code Tests >> Test TC-128A - Closed Loop Temp Not Reached
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Test TC-128A - Closed Loop Temp Not Reached

NOTE: For connector terminal ID, see CONNECTOR IDENTIFICATION  Directory. For wiring diagram, see appropriate WIRING DIAGRAMS - NON-TURBO article.
  1. This test procedure is not valid if thermostat is stuck open. If thermostat is operating correctly, go to next step. If thermostat is not operating correctly, replace thermostat. Perform TEST VER-2A.
  2. CLOSED LOOP TEMP NOT REACHED DTC sets if engine temperature does not rise to more than 60°F (16°C) within 10 minutes after engine is started. Possible causes are:
    • Thermostat failure
    • Engine Coolant Temperature (ECT) failure
    • Extremely cold ambient temperature conditions
    • Powertrain Control Module (PCM) failure.
  3. Turn ignition off. Disconnect PCM connector. Inspect PCM connector for damaged or pushed out terminals. Repair PCM connector as necessary. Perform TEST VER-2A. If PCM connector is okay, go to next step.
  4. Using an external ohmmeter, connect one ohmmeter lead to PCM connector terminal No. 26 ECT sensor signal circuit. Connect other ohmmeter lead to PCM connector terminal No. 43 ECT sensor ground circuit. See PCM TERMINAL 26 & 43 CONNECTOR WIRE ID table. If resistance is less than 11 k/ohms, replace PCM. Perform TEST VER-2A. IF resistance is 11 k/ohms or more, replace ECT sensor. Perform TEST VER-2A.
PCM TERMINALS 26 & 43 CONNECTOR WIRE IDENTIFICATION

Application Wire Color
PCM Terminal No. 26 (ECT Sensor Signal Circuit) Dark Green/White
PCM Terminal No. 43 (ECT Sensor Ground Circuit) Black/Dark Green
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