Has the fault been addressed?

If the above actions have not addressed the customer concern, develop a plan to manually diagnose the fault. Actions and information such as the following may help support this process

• Evaluate the symptoms and conditions described by the customer
• Evaluate driver information such as messages or telltales not previously investigated
• Review any available system descriptions, other service or training information to develop an understanding of the system related to the fault
• Review wiring schematics to identify system power, ground/earth, inputs, outputs circuits, identify if there are points in the wiring where multiple circuits are joined together
• Identify if any components, connectors or wiring harnesses that are exposed to extreme environmental conditions such as temperature, moisture or corrosive elements
• Use SCAN TOOL "Data Flow" to review parameters within an ECU to see if there is any unexpected data, and use the "10 Control" to exercise different inputs and outputs from an ECU to see if there is any unusual behavior that can be caused or controlled

Refer to the following service information or technical bulletins for further information:

• SYMPTOMS - ALL VEHICLE FAULTS
• Intelligent Diagnostic System (SCAN TOOL) setup and operation