NANO

602 ELECTRICAL 8.2 GENERAL PRECAUTIONS 1. Before starting electrical checks on the vehicle, ensure that the relevant mechanical functions & the relevant test equipment are working correctly. 2. Switch off ignition prior to making any connection or disconnection in the system as electrical surge caused by disconnecting ’live’ connections can damage electronic components. 3. Ensure hands and work surfaces are clean and free of grease, scarf, etc. as grease collects dirt which can cause tracking or high-resistance contacts. When handling printed circuit boards, treat them as you would a disc - hold by the edges only; note that some electronic components are susceptible to body static. 4. Connectors should never be subjected to forced removal or refit, especially inter-board connectors, damaged contacts will cause short-circuit and open-circuit conditions. Prior to commencing test, and periodically during test, touch a good earth, i.e. cigar lighter socket, to discharge body static as some electronic components are vulnerable to static electricity. 5. Secure the wiring harness 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. 6. If any section of a wiring harness interferes with the edge of a part or a corner, replace the part of harness or wrap the section of the harness with core tube. 7. To prevent damage to the electrical / electronic parts (especial ly computers or semi conductors) or to prevent fire : a. Always disconnect the battery. Ensure that battery leads are routed correctly and are not close to any potential chafing points. Never reverse connect the vehicle battery and always observe the correct polarity when connecting test equipment. b. When disconnecting the battery terminals, be sure for the following. 1. Turn off the ignition switch and all other switches. 2. Disconnect the negative (-) terminal wire and 3. Disconnect the positive (+) terminal wire. Connect the wires in the reverse order of disconnecting.