Flow of Diagnosis

Flow Of Diagnosis:

HOW TO TROUBLESHOOT ECM CONTROLLED SYSTEMS
In general, the ECM controlled system is considered to be a very intricate system requiring a high level of technical knowledge and expert skill to troubleshoot. However, the fact is that if you proceed to inspect the circuits one by one, troubleshooting of these systems is not complex. If you have adequate understanding of the system and a basic knowledge of electricity, accurate diagnosis and necessary repair can be performed to locate and fix the problem.

HOW TO PROCEED WITH TROUBLESHOOTING
- Carry out troubleshooting in accordance with the Flow of Diagnosis. Only the basic procedure is shown in the flow chart. Details are provided in each section, showing the most effective methods for each circuit. Confirm the troubleshooting procedures first for the relevant circuit before beginning troubleshooting of that circuit.

The following sentances breifly describe the steps shown in the Flow of Diagnosis.

[1] Ask the customer about the conditions and the environment when the problem occurred.

[2], [3] Confirm the symptoms and the problem conditions, and check the diagnostic trouble codes.
- When the problem symptoms do not appear during confirmation, use the symptom simulation method described in "How To Use The Flow Of Diagnosis", under "OEM Diagnostic Procedures".
Testing and Inspection

[4], [5], [6] Check the results obtained in Step [2] then confirm the inspection procedure for the system or the part which should be checked using the "Trouble Code Chart" (under Diagnostic Charts) or the Matrix Chart Of Problem Symptoms (under Diagnosis By Symptom).
Refer to Computers and Control Systems testing procedures.

[7] Check and repair the affected system or part in accordance with the instructions in Step (6).

[8] After completing repairs, confirm that the problem has been eliminated.
- If the problem is not reproduced, perform the confirmation test under the same conditions and in the same environment as when it occurred for the first time.

- For a more detailed explanation of these steps, refer to "How To Use The Flow Of Diagnosis", under OEM Diagnostic Procedures.