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Home >> Chevrolet >> 2001 >> Prizm Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Self-Diagnostics - 1.8L >> Diagnostic Tests >> DTC P0115: ECT Sensor Circuit >> Diagnostic Procedures
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Diagnostic Procedures

  1. Perform powertrain diagnostic system check. See POWERTRAIN DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check, go to next step.
  2. Using scan tool, monitor ECT sensor parameter. If ECT sensor value is 284°F (140°C) or greater, go to step  5. If ECT sensor value is less than 284°F (140°C), go to next step.
  3. Using scan tool, monitor ECT sensor parameter. If ECT sensor value is -40°F (-40°C) or less, go to step  7. If ECT sensor value is greater than -40°F (-40°C), go to next step.
  4. Using scan tool, clear DTC information and place vehicle into check mode. Operate vehicle within FREEZE FRAME conditions. If DTC resets, go to step  2. If DTC does not reset, see DIAGNOSTIC AIDS .
  5. Disconnect ECT sensor harness connector. Using scan tool, monitor ECT sensor parameter. If ECT sensor value is -40°F (-40°C), go to step  13. If ECT sensor value is not -40°F (-40°C), go to next step.
  6. Turn ignition off. Disconnect PCM harness connector. Check for short to ground in White wire between ECT sensor harness connector and PCM harness connector C2 terminal No. 14 for 4-speed A/T or No. 4 for except 4-speed A/T. See Figure or Figure . Check for short between White and Brown wires is ECT sensor circuit. Repair as necessary. After repairs, go to step  15. If circuit is okay, go to step  14.
  7. Disconnect ECT sensor harness connector. Using a fused jumper wire, jumper ECT sensor harness connector terminals. Using scan tool, monitor ECT sensor parameter. If ECT sensor value is 284°F (140°C) or greater, go to step  9. If ECT sensor value is less than 284°F (140°C), go to next step.
  8. Using a fused jumper wire, jumper ECT sensor harness connector terminal No. 2 (White wire) to ground. Using scan tool, monitor ECT sensor parameter. If ECT sensor value is 284°F (140°C) or greater, go to step  10. If ECT sensor value is less than 284°F (140°C), go to step  11.
  9. Check for poor connections at ECT sensor connector. Repair as necessary. After repairs, go to step  15. If connections are okay, go to step  13.
  10. Turn ignition off. Disconnect PCM harness connector. Check for open in Brown wire between ECT sensor and PCM harness connector C2 terminal No. 18 for 4-speed A/T or terminal No. 9 for except 4-speed A/T. See Figure or Figure or . Repair as necessary. After repairs, go to step  15. If circuit is okay, go to step  12.
  11. Turn ignition off. Disconnect PCM harness connector. Check for open or short in White wire between ECT sensor harness connector and PCM harness connector C2 terminal No. 14 for 4-speed A/T or No. 4 for except 4-speed A/T. See Figure or Figure . Repair as necessary. After repairs, go to step  15. If circuit is okay, go to next step.
  12. Check for poor connections at PCM. Repair as necessary. After repairs, go to step  15. If connections are okay, go to step  14.
  13. Turn ignition off. Replace ECT sensor. After replacing sensor, go to step  15.
  14. Replace PCM. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After replacing PCM, go to next step.
  15. Turn ignition on, with engine off. Using scan tool, clear DTC information. Road test vehicle within conditions for running DTC. See CODE ENABLE CRITERIA . Check for DTCs. If no DTCs are stored, repair is complete. If any DTCs are stored, diagnose affected DTCs.
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