Servicing the Electrical System

1. Prior to servicing the electrical system, be sure to turn off the ignition switch and disconnect the battery ground cable.

NOTE: In the course of MFI or ELC system diagnosis, when the battery cable is removed, any diagnostic code retained by the computer will be cleared. Therefore, if necessary read the diagnostic codes before removing the battery cable.




2. Secure the wiring harnesses by using clamps so that there is no slack. However, for any harness which passes to the engine or other vibrating parts of the vehicle, allow some slack within a range that does not allow the engine vibrations to cause the harness to come into contact with any of the surrounding parts, and then secure the harness by using a clamp.




3. If any section of a wiring harness interferes with the edge of a part, or a corner, wrap the section of the harness with tape or something similar in order to protect it from damage.




4. When installing any of the vehicle parts, be careful not to pinch or damage any of the wiring harnesses.




5. Never throw the relays, sensors and electrical parts, or expose them to strong shocks.




6. The electronic parts used in the computer, relays, etc. are easily damaged by heat. If there is a need for service operations that may cause the temperature to exceed 80 °C (176 °F), remove the electronic parts beforehand.




7. Loose connectors could troubles. Make sure that the connectors are connected securely.




8. When disconnecting a connector, be sure to pull only the connector, not the harness.




9. Disconnect connectors which have catches by pressing in the direction indicated by the arrows in the illustration.




10. Connect connectors which have catches by inserting the connectors until a "click" noise is heard.




11. When using a circuit tester to perform continuity or voltage checks on connector terminals, insert the test probe from the harness side. If the connector is a sealed connector, insert the test probe in through the hole in the rubber cap for the electrical wires, being careful not to damage the insulation of the wires and continue to insert the test probe until it contacts the terminal.




12. To avoid overloading the wiring, take the electrical current load of the optional equipment into consideration, and determine the appropriate wire size.