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Home >> Infiniti >> 2004 >> QX56 AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 213 (Body Control Modules) >> Self-Diagnostic System >> Manual Transaxle Diagnostic System Check >> Test Procedure
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Test Procedure

WARNING: This page is about a different car, the 2002 Pontiac Grand Am and 2002 Oldsmobile Alero. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: DO NOT perform this test if no driveability condition exists. Search for applicable bulletins before proceeding with diagnosis. Do not turn ignition switch to OFF position when performing this diagnostic procedure. DO NOT clear DTCs unless scan tool instructs service technician to do so. If there is a problem with starter system, go to appropriate STARTERS article in STARTING & CHARGING SYSTEMS. Ensure battery is fully charged and cables are clean and tight. Ensure PCM grounds are clean, tight, and in proper location.
  1. Connect scan tool to Data Link Connector (DLC). DLC is located under driver side of instrument panel. Turn ignition switch to RUN position. If scan tool powers up, go to next step. If scan tool does not power up, go to TEST A: SCAN TOOL DOES NOT POWER UP  under SYSTEM TESTS.
  2. Using scan tool, attempt to communicate with Powertrain Control Module (PCM). If scan tool displays PCM data, go to next step. If scan tool does not display PCM data, go to TEST B: SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE  under SYSTEM TESTS.
  3. Attempt to start vehicle. If engine starts and continues to run, go to next step. If engine does not start and continue to run, repair by symptom. See appropriate BASIC DIAGNOSTIC PROCEDURES - CARS - EXCEPT PRIZM article in ENGINE PERFORMANCE.
  4. Using scan tool, select DISPLAY DTCS function and retrieve any Body Control Modules (BCM) and PCM DTCs. If scan tool displays any PCM DTCs, go to next step. If scan tool does not display any PCM DTCs, go to step  7 .
  5. Using scan tool, record freeze frame and failure records information. After completing action, go to next step.
  6. If scan tool displays DTCs P0601, P0602 or P1621, perform appropriate test. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. If any other DTCs are displayed, perform appropriate test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS  .
  7. If no BCM DTCs are retrieved, go to next step. If any BCM DTCs are retrieved, perform appropriate test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS  .
  8. If customer concern does not appear to be Inspection/Maintenance (I/M) testing related, go to next step. If customer concern appears to be I/M testing related, perform inspection/maintenance system test. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
  9. Ensure engine is at normal operating condition. Compare scan tool data with typical values shown on scan tool data list. If display values are normal or within typical ranges, go to next step. If display values are not normal or within typical ranges, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS  .
  10. If customer concern is engine performance related, see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. Transaxle must be diagnosed by symptom. See SERVICING - M/T article in TRANSAXLE/TRANSMISSION. If no symptoms are evident system is okay at this time.
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