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Home >> Infiniti >> 2004 >> QX56 AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 213 (Body Control Modules) >> Self-Diagnostic System >> Powertrain Control Module Diagnostic System Check (3.4L) >> 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, repair starter system as necessary. See 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. 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. Turn ignition switch to RUN position. Using scan tool, attempt to communicate with Body Control Module (BCM), Electronic Brake Control Module (EBCM), Instrument Panel Cluster (IPC) and Powertrain Control Module (PCM). If scan tool communicates with BCM, EBCM, IPC and PCM, go to next step. If scan tool does not communicate with BCM, EBCM, IPC and PCM, go to TEST B: SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE  under SYSTEM TESTS.
  3. Attempt to start and idle engine. If engine starts and idles, go to next step. If engine does not start and idle, repair by symptom. See BASIC DIAGNOSTIC PROCEDURES - CARS - EXCEPT PRIZM article in ENGINE PERFORMANCE.
  4. Using scan tool, select DISPLAY DTCS function and retrieve any BCM, EBCM, IPC and PCM DTCs. If scan tool displays any DTCs, go to next step. If scan tool does not display any DTCs, go to step  9 .
  5. Using scan tool, select CAPTURED INFO function, and store PCM DTC information. After completing action, go to next step.
  6. If scan tool does not display any DTCs which begin with a "U", go to next step. If scan tool displays any DTCs which begin with a "U", go to TEST B: SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE  under SYSTEM TESTS.
  7. If scan tool does not display DTCs P0601 or P0602, go to next step. If scan tool displays DTCs P0601 or P0602, perform appropriate test. See SELF-DIAGNOSTICS - 3.4L ALERO, GRAND AM, IMPALA & MONTE CARLO article in ENGINE PERFORMANCE.
  8. If scan tool does not display DTCs P0560 or P0620, perform appropriate test. See SELF-DIAGNOSTICS - 3.4L ALERO, GRAND AM, IMPALA & MONTE CARLO article in ENGINE PERFORMANCE. If scan tool displays DTCs P0560 or P0620, perform appropriate test. See appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS.
  9. If customer concern appears not to be transaxle related, go to next step. If customer concern appears to be transaxle related, repair transaxle related concern. See appropriate article in TRANSMISSION/TRANSAXLE.
  10. If customer concern appears not 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 SELF-DIAGNOSTICS - 3.4L ALERO, GRAND AM & SUNFIRE article in ENGINE PERFORMANCE.
  11. If customer concern is hard start surges, lack of power, sluggishness, detonation/spark knock, hesitation, sag, stumble, cuts out, misses, has poor fuel economy, rough, unstable, incorrect idle, stalling, dieseling, run-on backfire, Malfunction Indicator Lamp (MIL) inoperative or MIL is always on, repair by symptom. See TROUBLE SHOOTING - NO CODES - CARS article in ENGINE PERFORMANCE. If no symptoms are evident, system is okay at this time.
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