ELECTRICAL PRECAUTIONS Battery disconnecting

ELECTRICAL PRECAUTIONS Battery disconnecting

The following [fender]guidelines are intended to Before disconnecting the battery, switch off all ensure the safety of the operator whilst preventing electrical equipment. damage to electrical and electronic components fitted to the vehicle. Battery charging

Polarity Recharge the battery out of the vehicle and keep the top well ventilated. While being charged or Never reverse connect the vehicle battery and always discharged, and for approximately 15 minutes observe the correct polarity when connecting test afterwards, batteries emit hydrogen gas which is equipment. flammable. Always ensure any battery charging area is well ventilated and that every precaution is taken to High voltage circuits avoid naked flames and sparks.

• WARNING: Before commencing work on
• an ignition system, all high tension
• terminals, adaptors and diagnostic

GENERAL PRECAUTIONS

equipment for testing should be inspected to ensure that they are adequately insulated and

Switch-off ignition prior to making any connection or

shielded to prevent accidental personal contacts

disconnection in the system as electrical surge

and minimize the risk of shock. Wearers of

caused by disconnecting ’live’ connections can

surgically implanted pacemaker devices should

damage electronic components.

not be in close proximity to ignition circuits or

Ensure hands and work surfaces are clean and free of

diagnostic equipment.

grease, swarf, etc. as grease collects dirt which can cause tracking or high-resistance contacts.

Whenever disconnecting live high tension circuits

When handling printed circuit boards, treat them as

always use insulated pliers and never allow the open

you would a disc - hold by the edges only.

end of a high tension lead to come into contact with

Prior to commencing a test, and periodically during a

other components particularly electronic control units.

test, touch a good earth, for instance, a cigar lighter

Exercise caution when measuring the voltage on the

socket, to discharge body static as some electronic

coil terminals while the engine is running, since, high

components are vulnerable to static electricity.

voltage spikes can occur on these terminals.

Connectors and harness

Always ensure that 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 note 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.