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Testing Procedure

WARNING: This page is about a different car, the 2003 Toyota Camry Solara. However, it is still accessible from the selected car via links, so may be relevant.

To ensure correct diagnosis and repair, testing should be done in the following sequence:

  1. Record Customer Complaint

    Ensure all customer complaints or observations are recorded. Test drive vehicle with customer when necessary for malfunction verification.
  2. DLC3 Inspection

    Connect scan tool to data link connector No. 3 (DLC3). See Fig 1. If the display indicates a communication fault in the tool, inspect the DLC3. See DATA LINK CONNECTOR NO. 3 INSPECTION  under SCAN TOOL PROBLEMS.
  3. Retrieve DTCs & Freeze Frame Data

    Retrieve diagnostic trouble codes (DTCs) and record any freeze frame data (if applicable). See RETRIEVING DIAGNOSTIC TROUBLE CODES  and FREEZE FRAME DATA  .
  4. Clear DTCs & Freeze Frame Data

    Clear DTCs and freeze frame data. See CLEARING DIAGNOSTIC TROUBLE CODES .
  5. Visual Inspection

    Inspect all connectors of suspect circuit or component. Ensure all connections are clean and tight.
  6. Check Mode Diagnosis

    Set check mode diagnosis. See CHECK MODE CODE RETRIEVAL (HAND-HELD TESTER ONLY)  under RETRIEVING DIAGNOSTIC TROUBLE CODES.
  7. Confirm Symptoms

    Perform road test. Determine if original symptoms are still present. If the engine does not start, perform steps  9 and  10 first. If a malfunction does not occur, simulate symptom and go to next step. If a malfunction occurs, go to next step.
  8. DTC Check

    Check the DTC. See SYSTEM OVERVIEW . If there is no code, go to next step. If there is a malfunction code, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS , then step  11.
  9. Basic Inspection

    Perform basic inspection. See BASIC INSPECTION . If the results are OK, go to next step. If the results are not good, inspect the parts and then proceed to step  13.
  10. Determine Symptom

    Determine problem symptoms. See SYMPTOM DIAGNOSIS under SYMPTOMS in TROUBLE SHOOTING - NO CODES article. If the problem is in the circuit, go to next step. If the problem is in the parts, inspect parts and go to step  13.
  11. Inspect Circuit

    Perform the appropriate circuit test. See DIAGNOSTIC TESTS . If the circuit is OK, go to step  13. If the circuit is not good, go to next step.
  12. Intermittent Problems Check

    Check for intermittent problems. See INTERMITTENT PROBLEM CHECK .
  13. Verification Procedure

    Identify problem and make necessary adjustments and repairs. After repairs have been completed, clear all DTCs from ECM. SeeCLEARING DIAGNOSTIC TROUBLE CODES . Perform road test. Ensure no DTCs are present and all symptoms and/or complaints have been repaired.

Fig 1: Connecting Hand-Held Tester To DLC3
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