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Home >> Chevrolet >> 1998 >> Astro Van Cargo, RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Diagnostic Trouble Codes >> DTC P0125 - ECT Excessive Time To Reach Closed Loop >> Diagnostic Procedures

Diagnostic Procedures

  1. Perform POWERTRAIN ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK . Retrieve and record FREEZE FRAME and/or FAIL RECORDS data for each DTC set. After performing OBD system check, go to next step.
  2. Allow engine to cool completely. Turn ignition on. Using scan tool, compare ECT and IAT values. If values are close, go to next step. If values are not close, go to DTC P0117 diagnosis.
  3. Start engine. Using scan tool, monitor ECT value. If ECT value rises steadily to greater than 95°F (35°C) within 9 minutes, see DIAGNOSTIC AIDS. If ECT value does not rise steadily to greater than 95°F (35°C) within 9 minutes, go to next step.
  4. Check coolant level. If coolant level is low, diagnose cooling system. If coolant level is okay, go to next step.
  5. Compare actual coolant temperature with scan tool ECT value. If temperatures are close, repair cooling system as necessary. If temperatures are not close, go to next step.
  6. Replace ECT sensor. After replacing sensor, go to next step.
  7. Using scan tool, select DTC, CLEAR INFO function. Start engine and allow it to reach operating temperature. Using scan tool, select DTC, SPECIFIC function and enter this DTC. Operate vehicle within conditions required to set DTC. If scan tool indicates that this DTC RAN AND PASSED, go to next step. If scan tool does not indicate that this DTC RAN AND PASSED, repeat step 2).
  8. Using scan tool, select Read and Record INFO, REVIEW INFO function. If any undiagnosed DTCs are displayed, diagnose affected DTCs. If no additional DTCs are displayed, system is okay.
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