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3.1L & 3.4L

NOTE: Check for applicable Technical Service Bulletins (TSBs) before proceeding. DO NOT perform the following procedure if driveability conditions are not present. DO NOT turn ignition off during the following procedure or clear DTCs unless instructed to do so.
  1. Turn ignition on, with engine off. Observe MIL. If MIL illuminates, go to next step. If MIL does not illuminate, go to MIL INOPERATIVE .
  2. Turn ignition off. Connect scan tool. Turn ignition on. If scan tool displays PCM data, go to next step. If scan tool does not display PCM data, go to DLC DIAGNOSIS OR NO SCAN TOOL DATA .
  3. Attempt to start engine. If engine starts and continues to run, go to next step. If engine does not start, or starts and stalls, go to NO START DIAGNOSIS in appropriate BASIC DIAGNOSTIC PROCEDURES article.
  4. Using scan tool, display LAST TEST FAIL information. If any DTCs are stored, save freeze frame and failure records information using scan tool CAPTURE INFO feature. If DTCs are indicated as last test failed, diagnose DTCs. See DIAGNOSTIC TESTS in appropriate TESTS W/CODES article. If DTCs are not indicated, go to next step.
  5. Using scan tool, display DTC FAILURE RECORDS information. If DTC failure records are stored, save freeze frame and failure records information using scan tool CAPTURE INFO feature. If failure records are stored, diagnose DTCs. See DIAGNOSTIC TESTS in appropriate TESTS W/CODES article. If failure records are not stored, go to next step.
  6. Compare PCM data values displayed on scan tool to typical engine scan data values. If values are within limits, system is okay. If values are not within limits, see appropriate SYSTEM & COMPONENT TESTING article.
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