Connectors - Ford Ranger Maintaince And Repair Manual

sandwiched between two sheets of plastic for more protection and flexibility. A complete printed circuit,
consisting of conductors, insulating material and connectors for lamps or other components is called a printed
circuit board. Printed circuitry is used in place of individual wires or harnesses in places where space is
limited, such as behind instrument panels.
Since automotive electrical systems are very sensitive to changes in resistance, the selection of properly sized
wires is critical when systems are repaired. A loose or corroded connection or a replacement wire that is too
small for the circuit will add extra resistance and an additional voltage drop to the circuit.
The wire gauge number is an expression of the cross−section area of the conductor. Vehicles from countries
that use the metric system will typically describe the wire size as its cross−sectional area in square
millimeters. In this method, the larger the wire, the greater the number. Another common system for
expressing wire size is the American Wire Gauge (AWG) system. As gauge number increases, area decreases
and the wire becomes smaller. An 18 gauge wire is smaller than a 4 gauge wire. A wire with a higher gauge
number will carry less current than a wire with a lower gauge number. Gauge wire size refers to the size of the
strands of the conductor, not the size of the complete wire with insulator. It is possible, therefore, to have two
wires of the same gauge with different diameters because one may have thicker insulation than the other.
It is essential to understand how a circuit works before trying to figure out why it doesn't. An electrical
schematic shows the electrical current paths when a circuit is operating properly. Schematics break the entire
electrical system down into individual circuits. In a schematic, usually no attempt is made to represent wiring
and components as they physically appear on the vehicle; switches and other components are shown as simply
as possible. Face views of harness connectors show the cavity or terminal locations in all multi−pin
connectors to help locate test points.

CONNECTORS

Three types of connectors are commonly used in automotive applications−weatherproof, molded and hard
shell.
Hard shell (left) and weatherproof (right) connectors have replaceable terminals
• Weatherproof−these connectors are most commonly used where the connector is exposed to the
elements. Terminals are protected against moisture and dirt by sealing rings which provide a
weathertight seal. All repairs require the use of a special terminal and the tool required to service it.
Unlike standard blade type terminals, these weatherproof terminals cannot be straightened once they
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