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How to Follow/Perform Trouble Diagnosis

How To Follow Flow Chart In Trouble Diagnoses:





NOTE: The flow chart indicates work procedures required to diagnose problems effectively. Observe the following instructions before diagnosing.

1. Use the flow chart after locating probable causes of a problem following the "Preliminary Check" or the "Symptom Chart".
2. After repairs, re-check that the problem has been completely eliminated.
3. Refer to Component Parts Location and Harness Layout for the System9 described In each section for Identification location of components and harness connectors.
4. Refer to the Circuit Diagram for Quick Pinpoint Check. If you must check circuit continuity between harness connectors In more detail, such as when a sub-harness is used.
5. When checking circuit continuity, Ignition switch should be "OFF".
6. Before checking voltage at connectors, check battery voltage.
7. After accomplishing the Diagnostic Procedures and Electrical Components Inspection, make sure that all harness connectors are reconnected as they were.



How To Follow This Flow Chart In Trouble Diagnoses:





Work and Diagnostic Procedure
Start to diagnose a problem using procedures indicated in enclosed blocks, as shown in the following example.


Measurement results
Required results are indicated in bold type in the corresponding block, as shown below:

These have the following meanings:

Battery voltage 11 - 14 Volts or approximately 12 Volts

Voltage: Approximately 0 Volts - Less than 1 Volt


Cross reference of work symbols in the text and illustrations
Illustrations are provided as visual aids for work procedures. For example, symbol (A) indicated in the left upper portion of each illustration corresponds with the symbol in the flow chart for easy identification. More precisely, the procedure under the "CHECK POWER SUPPLY" outlined previously is indicated by an illustration (A).

Symbols used in illustrations
Symbols included in illustrations refer to measurements or procedures. Before diagnosing a problem, familiarize yourself with each symbol.
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