About System Pre-Check

NOTE: It is imperative that this procedure be performed first. Failure to do so may result in incorrect diagnosis of problem, wasted time, and improper replacement of good components.

The system pre-check is used to screen a vehicle for relatively simple diagnostic repairs such as loose connectors, blown fuses, etc. However, the system pre-check is also used to prepare the vehicle for further diagnostics. In addition, warning lamp concerns are dealt with in this test.