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Home >> Chevrolet >> 2002 >> Monte Carlo LS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Self-Diagnostics - 3.4L >> Self-Diagnostic System >> Diagnostic System Check - Engine Controls >> Diagnostic Procedures
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Diagnostic Procedures

  1. Install scan tool. Does the scan tool power-up? If yes, go to next step. If no, perform SCAN TOOL DOES NOT POWER UP IN DATA LINK COMMUNICATIONS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
  2. Turn ON ignition, with engine OFF. Attempt to establish communication with the PCM, Body Control Module (BCM), Instrument Panel (IP) cluster, and Electronic Brake Control Module (EBCM). If you are using a Tech 2, obtain the information using the Class 2 Message Monitor feature. Does the scan tool communicate with all of the control modules? If yes, go to next step. If no, perform SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
  3. Attempt to start engine. Does engine start and idle? If yes, go to next step. If no, go to NO-START DIAGNOSIS in appropriate BASIC DIAGNOSTICS PROCEDURES article.
  4. Select the DTC display function for the PCM, BCM, IP cluster and EBCM. Does scan tool display any DTCs? If yes, go to next step. If no, go to step  9.
  5. With a scan tool, select Captured Info in order to store the powertrain DTC information. When complete, go to next step.
  6. Does scan tool display DTCs which begin with a "U"? If yes, go to next step. If no, perform SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE appropriate BASIC DIAGNOSTICS PROCEDURES article.
  7. Does scan tool display DTC P0601or P0602? If yes, go to DTC P0601-P0607, P1600, P1621, P1627, P1680, P1681 OR P1683: CONTROL MODULE READ ONLY MEMORY . If no, go to next step.
  8. Does scan tool display DTC P0560 or P0620? If yes, diagnose affected DTC(s). See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, go to next step.
  9. Is customer's concern related to the automatic transmission? If yes, diagnose transmission. See appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS. If no, go to next step.
  10. Is customer's concern with Inspection/Maintenance (I/M) testing? If yes, go to INSPECTION/MAINTENANCE SYSTEM CHECK  under INSPECTION/MAINTENANCE PROCEDURES. If no, go to next step.
  11. Check for the following symptoms: Hard start, surges/chuggles, lack of power, sluggishness/sponginess, detonation/spark knock, hesitation, sag, stumble, cuts out, misses, poor fuel economy, poor fuel fill quality, rough idle, unstable idle, incorrect idle, stalling, dieseling, run-on, backfire, Malfunction Indicator Light (MIL) inoperative, or MIL always on. Did you find and correct the condition? If yes, system is okay. If no, problem is intermittent. See INTERMITTENT CONDITIONS  under SELF-DIAGNOSTIC SYSTEM.
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