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Diagnostic Procedures

NOTE:
  • Do not perform this diagnostic if there is not a driveability concern, unless another procedure directs you to this diagnostic
  • Before you proceed with diagnosis, search for applicable service bulletins
  • Unless a diagnostic procedure instructs you, do NOT clear the DTCs.
  • If there is a condition with the starting system, see appropriate STARTERS article in ENGINES.
  • Ensure the battery has a full charge.
  • Ensure the battery cables are clean and tight.
  • Ensure the ECM grounds are clean, tight, and in the correct location.
  1. Install a scan tool. Does the scan tool turn ON? If yes, go to next step. If no, see SCAN TOOL DOES NOT POWER UP in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
  2. Turn ignition ON, with engine OFF. Attempt to establish communication with the control module. Does the scan tool communicate with the control module? If yes, go to next step. If no, see SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
  3. Attempt to start the engine. Does the engine start and idle? If yes, go to next step. If no, see ENGINE CRANKS BUT DOES NOT RUN under NO-START DIAGNOSIS in BASIC DIAGNOSTIC PROCEDURES - 3.0L SATURN "L" SERIES article.
  4. Select DTC Information on the scan tool. does the scan tool display any Powertrain DTCs? If yes, go to next step. If no, go to step  7.
  5. With the scan tool, save or capture the Powertrain DTC Information, Store Information. Did you save or capture the Powertrain DTC Information, Store Information? If yes, go to next step.
  6. If scan tool displays DTC P0601-P0607, P1600, P1621, P1627, P1680, P1681 & P2610: ECM MEMORY, see DTC P0601-P0607, P1600, P1621, P1627, P1680, P1681 & P2610: ECM MEMORY  under DIAGNOSTIC TESTS. If scan tool does not display DTC P0602, see DIAGNOSTIC TROUBLE CODE DEFINITIONS .
  7. If customer's concern is with the automatic transmission, see appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS. If customer's concern is not with the automatic transmission, go to next step.
  8. If customer's concern is with Inspection and Maintenance (I/M) testing, see INSPECTION/MAINTENANCE SYSTEM CHECK  under DRIVE CYCLES. If no, go to next step.
  9. If no DTCs exist, perform diagnosis by symptom. See SYMPTOMS in TROUBLE SHOOTING - NO CODES - 3.0L SATURN "L" SERIES article.

    If Malfunction Indicator Light (MIL) is inoperative, see MALFUNCTION INDICATOR LIGHT INOPERATIVE  under SYSTEM TEST. If MIL is always on, see MALFUNCTION INDICATOR LIGHT ALWAYS ON  under SYSTEM TEST. Did you find and correct the condition? If yes, system is okay. If no, see INTERMITTENT CONDITIONS .

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