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Powertrain Diagnostic System Check

NOTE: Check for applicable Technical Service Bulletins (TSB) 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. If vehicle does not crank, 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. Install scan tool. If scan tool turns on, go to next step. If scan tool does not turn on, see SCAN TOOL DOES NOT POWER UP under SYSTEM TESTS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
  2. Turn ignition on, engine off. Attempt to establish communication with specified class 2 modules. See CLASS 2 MODULES table. If scan tool communicates with all control modules, go to next step. If scan tool does not communicate with all control modules, see SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE under SYSTEM TESTS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
  3. Attempt to start engine. If engine starts and idles, go to next step. If engine does not start and idle, see appropriate BASIC DIAGNOSTIC PROCEDURES article.
  4. Select DTC display function for specified class 2 modules. See CLASS 2 MODULES table. If DTCs are present, go to next step. If DTCs are not present, go to step  9.
  5. Using scan tool, select CAPTURE INFO to store powertrain DTC information. Go to next step.
  6. If scan tool displays DTCs which begin with "U", see SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE under SYSTEM TESTS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT. If scan tool does not display DTCs which begin with "U", go to next step.
  7. If scan tool displays DTC P0601 or P0602, go to DTC P0601: PCM INTERNAL PROGRAM FAULT  or DTC P0602: PCM NOT PROGRAMMED  under DIAGNOSTIC TESTS.
  8. If scan tool displays DTC P0560 or P0620, see appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS. If scan tool does not display DTC P0560 or P0620, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS .
  9. If customer's concern is with the automatic transmission, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS article. If customer's concern is not with the automatic transmission, go to next step.
  10. If customer's concern is with Inspection/Maintenance (I/M) testing, go to INSPECTION/MAINTENANCE SYSTEM CHECK  under INSPECTION/MAINTENANCE PROCEDURES. If customer's concern is driveability, see appropriate TROUBLE SHOOTING - NO CODES article.
CLASS 2 MODULES

Application Modules
Alero, Grand Am, Impala & Monte Carlo PCM, Body Control Module (BCM), Instrument Panel Cluster (IPC) & Electronic Brake Control Module (EBCM)
Century PCM, (1) HVAC Module, Instrument Panel Cluster (IPC), Electronic Brake Control Module (EBCM) & Vehicle Theft Deterrent (VTD) Module
Grand Prix PCM, (2) Instrument Panel Cluster (IPC) & Vehicle Theft Deterrent (VTD) Module
Malibu PCM, Body Control Module (BCM), Electronic Brake Control Module (EBCM) & Vehicle Theft Deterrent (VTD) Module
(1) If equipped with automatic temperature control.
(2) If equipped with Heads Up Display (HUD).
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