Initial Inspection and Diagnostic Overview

The Diagnostic Test Procedures consist of DIAGNOSIS and TEST PROGRAMS for electronically controlled systems.

DIAGNOSIS:
- Function Test - Provides a quick and easy inspection of the system.

- Diagnostic Trouble Code (DTC) Memory - Narrows down the test procedure through means of reading out the stored DTC's.

- Diagnostic Chart - Shows you where to enter the test when the system failure is not indicated with a DTC.

NOTE: The Diagnosis references you directly to the appropriate Test.

TEST PROGRAM:
The Test Program is divided into Electrical and Pneumatic Test Groups, depending upon the system. Each Test Group contains a Component Location, Preparation For Test and a Test section.

- Component Locations - The location of components referenced in the test are shown.

- Preparation For Test - Shows all equipment, special tools and references to ensure a smooth execution of the test.

- Test - Performing the test. As a rule, enter the test via diagnosis. Consists of primary and secondary test steps, test values.

NOTE:
- Prior to performing a Test, review the Component Locations and Preparation for Test sections.
- Depending upon the particulars of the case, the Test Program will direct you accordingly.
- All Diagnostic troubleshooting must begin by "CHECKING THE BASICS". Certain basic faults can be undetectable by the self-diagnostic system of the ACC control unit.
- When a wire is listed in the "Possible cause/Remedy" column, all connectors between the control unit and the component being tested are to be included as a possible failure source.
- When using the 126 socket Socket Box Tester, see the appropriate wiring diagram for a description of the socket nomenclature.