Technician Safety Information
Electrical Precautions
General
The following guidelines are intended to ensure the safety of the operator whilst preventing damage to the electrical and electronic components fitted to the vehicle. Where necessary specific precautions are detailed in the relevant sections of this Manual which should be referred to prior to commencing repair operations.
Equipment - Prior to commencing any test procedure on the vehicle ensure that the relevant test equipment is working correctly and any harness or connectors
are in good condition. This particularly applies to mains lead and plugs.
WARNING: Before commencing work on an ignition system all high tension terminals, adaptors and diagnostic equipment for testing should be inspected to ensure that they are adequately insulated and shielded to prevent accidental personal contacts and minimize the risk of shock. Wearers of surgically implanted pacemaker devices should not be in close proximity to ignition circuits or diagnostic equipment.
Polarity - Never reverse connect the vehicle battery and always observe the correct polarity when connecting test equipment.
High Voltage Circuits - Whenever disconnecting live ht circuits always use insulated pliers and never allow the open end of the ht lead to come into contact with other components, particularly ECU's. Exercise caution when measuring the voltage on the coil terminals while the engine is running, as high voltage spikes can occur on these terminals.
Connectors and Harness - The engine compartment of a vehicle is a particularly hostile environment for electrical components and connectors. Always ensure these items are dry and oil free before disconnecting and connecting test equipment. Never force connectors apart either by using tools or by pulling on the wiring harness. Always ensure locking tabs are disengaged before removal and not orientation to enable correct reconnection. Ensure that any protective covers and substances are replaced if disturbed.
Having confirmed a component to be faulty, switch off the ignition and disconnect the battery. Remove the component and support the disconnected harness. When replacing the component keep oily hands away from electrical connection areas and push connectors home until any locking tabs fully engage.
Battery disconnecting
Before disconnecting the battery, switch off all electrical equipment. If the radio is to be serviced, ensure the security code has been deactivated.
CAUTION: To prevent damage to electrical components ALWAYS disconnect the battery when working on the vehicle electrical system. The earth lead must be disconnected first and reconnected last. Always ensure that battery leads are routed correctly and are not close to any potential chafing points.
Battery charging
Recharge the battery out of the vehicle and keep the top well ventilated. While being charged or discharged, and for approximately fifteen minutes afterwards, batteries emit hydrogen gas. This gas is inflammable.
Always ensure any battery charging is well ventilated and that every precaution is taken to avoid naked flames and sparks.
Jump starting
WARNING: Hydrogen and oxygen gases are produced during normal battery operation. This gas mixture can explode if flames, sparks or lighted tobacco are brought near battery. When charging or using a battery in an enclosed space, always provide ventilation and shield your eyes.
Keep out of reach of children. Batteries contain sulphuric acid. Avoid contact with skin, eyes, or clothing. Also, shield eyes when working near battery to protect against possible splashing of acid solution. In case of acid contact with skin, eyes, or clothing, flush immediately with water for a minimum of fifteen minutes. If acid is swallowed, drink large quantities of milk or water, followed by milk of magnesia, a beaten egg, or vegetable oil. SEEK MEDICAL AID IMMEDIATELY.
To Jump Start - Negative Ground Battery
WARNING: To avoid any possibility of injury use particular care when connecting a booster battery to a discharged battery.
1. Position vehicles so that jump leads will reach, ensuring that vehicles DO NOT TOUCH, alternatively a fully charged slave battery may be positioned on floor adjacent to vehicle.
2. Ensuring that ignition and all electrical accessories are switched off, that parking brake is applied and neutral is selected on a manual gearbox, with an automatic gearbox select neutral (N) or park (P) and then connect the jump leads as follows;
A. Connect one end of first jumper cable to positive (+) terminal of booster battery.
B. Connect other end of first jumper cable to positive (+) terminal of discharged battery.
C. Connect one end of second jumper cable to negative terminal of booster battery.
D. Connect other end of second jumper cable to a good earth point on the engine, NOT TO NEGATIVE TERMINAL OF DISCHARGED BATTERY. Keep jumper lead away from moving parts, pulleys, drive belts and fan blade assembly.
WARNING: Making final cable connection could cause an electrical arc which if made near battery could cause an explosion.
3. If booster battery is installed in another vehicle, start engine and allow to idle.
4. Start engine of vehicle with discharged battery, following starting procedure in Owners' Manual.
CAUTION: If vehicle fails to start within a maximum time of 12 seconds, switch ignition off and investigate cause. Failing to follow this instruction could result in irrepairable damage to catalysts.
5. Remove negative (-) jumper cable from the engine and then terminal of booster battery.
6. Remove positive (+) jumper cable from positive terminals of booster battery and discharged battery.
Disciplines
Switch off ignition prior to making any connection or disconnection in the system as electrical surge caused by disconnecting 'live' connections can damage electrical components.
Ensure hands and work surfaces are clean and free of grease, swarf, 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.
Connectors should never be subjected to forced removal or refit, especially inter-board connectors, as 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.
Grease for electrical connectors
All underbonnet and underbonnet connectors are protected against corrosion by the application of a special grease on production. Should connectors be disturbed in service, repaired or replaced, a grease of this type (available in 150gm tubes under Part No. BAU 5811) should again be applied.
NOTE: The use of other greases must be avoided as they can migrate into relays, switches etc., contaminating the contacts and leading to intermittent operation or failure.