About This Document

General
This document is intended to assist in diagnosing electrical faults, and should be used in conjunction with the Electrical Circuit Diagrams. The document is divided into the following.
1. INTRODUCTION - Includes Electrical Precautions, a list of Abbreviations and general information on how to use this document.
2. FUSE DETAILS - Provides details of location, rating in Amperes, and circuit(s) protected.
3. EARTH POINTS AND HEADERS - Provides details of earth points and earth headers, including a plan view of the vehicle to aid location.
4. DESCRIPTION AND OPERATION - Provides an explanation of how each of the systems operate.
5. CIRCUIT REFERENCE NUMBERS - Provides a list of circuit reference numbers against a model or feature to which they apply.
6. CONNECTOR DETAIL - Details of connectors including a location photograph, face view and pin-out table.


NOTE: Before starting electrical checks on the vehicle, ensure that relevant mechanical functions operate satisfactorily.


References
References to the LH or RH side given in this document are made when viewing the vehicle from the rear.

Operations covered in this document do not include reference to testing the vehicle after repair. It is essential that work is inspected and tested after completion and, if necessary, a road test of the vehicle is undertaken, particularly where safety related items are concerned.


CAUTION: Before undertaking any electrical work on a vehicle ALWAYS read the ELECTRICAL PRECAUTIONS.


Battery Voltage

Open Circuit Voltage Test
Before commencing diagnosis of electrical problems, verify the condition of the battery is acceptable by using the open circuit voltage test.
1. Switch off all electrical loads on the vehicle.
2. Adjust digital multimeter to read dc volts on the appropriate scale.
3. Connect test probes across battery terminals ensuring that polarity is correct and record the voltage displayed.

A reading of 12.3 V or more is acceptable; any battery which reads less than this will need charging.


NOTE: If the vehicle has been used within a period of 8 hours prior to the test, surface charge must be removed from the battery by switching the headlamps on for approximately 30 seconds. Wait a further 60 seconds before checking the open circuit voltage.


Battery voltage is used as a known reference for ascertaining whether or not circuits are receiving sufficiently high voltage for components to function correctly. This reference is only a guide since most electronic circuits are designed to function over a wide range of voltages. In addition, consideration must be given to readings affected by voltage drop across certain components and fluctuations due to cable lengths.