A good understanding of the malfunction conditions can make troubleshooting faster and more accurate.
In general, each customer feels differently about a malfunction. It is important to fully understand the symptoms or conditions for a customer complaint.

Information from Customer.
- WHAT..... Vehicle model.
- WHEN..... Date, Frequencies.
- WHERE..... Road conditions.
- HOW..... Operating conditions, Symptoms.

Preliminary Check.
Check that the following parts are in good order.