Chapter 19 Introduction

Introduction

Normally there will already be a diagnostic routine developed in the service information for specific system faults on an automobile or truck. It is always best to follow these diagnostic routines rather than developing your own diagnostics. However, sometimes the diagnostic routine in the service information does not work, or there is no diagnostic routine for the situation you are experiencing. This chapter walks you through the steps of developing your own diagnostics for these situations.

Developing a good diagnostic thought process for troubleshooting automotive electrical/mechanical problems involves three basic steps:

  • Developing a written or mental list of all the possible causes of the customer concern.

  • Obtaining as much information as possible to eliminate items from the fault list.

  • Prioritize the remaining items

Once the items on the list have been reduced and prioritized, diagnosis of the concern can begin. This process may take a little time up-front before beginning diagnosis; however, it can reduce wasted time, unnecessary parts, and misdiagnosis, resulting in a satisfied customer and a good reputation.