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Vehicle Damage Warnings

ELECTROSTATIC DISCHARGE DAMAGE
Electronic components used in control systems are often designed to carry very low voltage, and are very susceptible to damage caused by electrostatic discharge. It is possible for less than 100 volts of static electricity to cause damage to some electronic components. By comparison, it takes as much as 4,000 volts for a person to even feel the zap of a static discharge.

ACQUIRING CHARGE
There are several ways for a person to become statically charged. The most common methods of charging are by friction and induction. An example of charging by friction is a person sliding across a car seat, in which a charge of as much as 25,000 volts can build up. Charging by induction occurs when a person with well-insulated shoes stands near a highly charged object and momentarily touches ground. Charges of the same polarity are drained off, leaving the person highly charged with the opposite polarity. Static charges of either type can cause damage, therefore, it is important to use care when handling and testing electronic components.


PREVENTING DAMAGE
To prevent possible electrostatic discharge damage:
^ Always touch a known good ground before handling an Engine Control Module (ECM).
^ Do not touch the ECM connector pins or soldered components on the ECM circuit board.