Ford Taurus, Руководство пользователя

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All vehicles covered in this manual are equipped with an alternating current
generator or alternator. Such units are more efficient than the generators used in
older vehicles, can be rotated at higher speeds, and have fewer brush problems.
In an alternator, the field rotates while all the current produced passes only
through the stator windings. The brushes bear against continuous slip rings rather
than a commutator. This prevents the current from traveling in the wrong
direction. A series of diodes is wired together to permit the alternating flow of the
stator to be converted to a pulsating, but unidirectional, flow at the alternator
output. The alternator's field is wired in series with the voltage regulator.
The regulator consists of several circuits. Each circuit has a core, or magnetic coil
of wire, which operates a switch. Each switch is connected to ground through one
or more resistors. The coil of wire responds directly to system voltage. When the
voltage reaches the required level, the magnetic field created by the winding of
the wire closes the switch and inserts a resistance into the generator field circuit,
thus reducing the output. The contacts of the switch cycle open and close many
times each second to precisely control voltage. Alternators are self-limiting as far
as maximum current is concerned.
Ignition System
There are two different types of ignition systems found on these vehicles. Most of
the vehicles utilize a Distributor Ignition (DI) system which incorporates a
conventional distributor. The SHO and the 3.0L Flexible Fuel (FF) vehicles utilize a
distributorless ignition system known as Electronic Ignition (EI).
For more information, testing and removal/replacement procedures
regarding the ignition systems, please refer to Section 2 of this manual.
Safety Precautions
Observing these precautions will help avoid damage to the vehicle's electrical
system and ensure safe handling of the system components:
z Be absolutely sure of the polarity of a booster battery before making connections.
Connect the cables positive-to-positive, and negative-to-a good ground. Connect
positive cables first and then make the last connection to an engine ground on the
vehicle with the dead battery so that arcing cannot ignite hydrogen gas that may
have accumulated near the battery. Even momentary connection of a booster
battery with the polarity reversed will damage alternator diodes.
z Disconnect both vehicle battery cables before attempting to charge a battery.
z NEVER ground the alternator output or battery terminal. Be cautious when using
metal tools around a battery to avoid creating a short circuit between the
terminals.
z NEVER run an alternator without load unless the field circuit is disconnected.
z NEVER attempt to polarize an alternator.
Alternator
ALTERNATOR PRECAUTIONS
To prevent damage to the on-board computer, alternator and regulator, the
following precautionary measures must be taken when working with the electrical
Стр . 3 из 46 ENGINE ELECTRICAL
18.11.2005 http://www.chiltondiy.com/content/8687/8687_3_1.html