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HOMESERVICE MANUALSTOYOTA2004CELICA GT, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 259 (INTRODUCTION)HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMSELECTRONIC CIRCUIT INSPECTION PROCEDURE
2004 Toyota Celica GT, Standard

Electronic Circuit Inspection Procedure

2004 Toyota Celica GT, StandardSECTION Electronic Circuit Inspection Procedure
WARNING: This page is about a different car, the 2002 Toyota Highlander. However, it is still accessible from the selected car via links, so may be relevant.
  1. Basic Inspection: 
    1. Resistance measuring condition of electronic parts:

      Unless stated, all resistance is measured at an ambient temperature of 20°C (68°F). Because the resistance may be outside the specifications if measured at high temperatures immediately after the vehicle has been running, measurements should be made when the engine has cooled down.

      2. NOTE: Water proof connector cannot be checked from its back side, check by connecting the sub-harness.

      Do not damage the terminals moving the inserted tester needle.

    2. Handling of connectors:
      1. When removing the connector with a lock, press the connector toward the engagement and remove the lock by making the lock claw movable easily.
        Fig 1: Identifying Correct Connector Handling Procedures
        G00397481Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. When removing the connector, do not hold the harness, but hold the connector.
      3. Before connecting the connector, check that there are no deformation, damaged and missing terminals.
      4. Connection of the connector with a lock should be securely done until it makes a click sound.
      5. In case of checking the connector with a Toyota electrical tester, perform it at the back side (harness side) of the connector using a mini test lead.
    3. Connector checking points:
      1. Checking when the connector is connected: By holding the connector, check the inserted condition and locking efficiency (engaged condition).
      2. Checking when the connector is removed: Check by pulling the wire harness lightly (missing terminal, terminal crimping condition, core wire break).
        Fig 2: Inspecting Terminal Ends
        G00397482Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        3. NOTE: When testing a gold-plated female terminal, always use a gold-plated male terminal.
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