Test Equipment; Jumper Wires - Ford Ranger Maintaince And Repair Manual

are bent. Make certain that the connectors are properly seated and all of the sealing rings are in place
when connecting leads.
• Molded−these connectors require complete replacement of the connector if found to be defective.
This means splicing a new connector assembly into the harness. All splices should be soldered to
insure proper contact. Use care when probing the connections or replacing terminals in them, as it is
possible to create a short circuit between opposite terminals. If this happens to the wrong terminal
pair, it is possible to damage certain components. Always use jumper wires between connectors for
circuit checking and NEVER probe through weatherproof seals.
• Hard Shell−unlike molded connectors, the terminal contacts in hard−shell connectors can be replaced.
Replacement usually involves the use of a special terminal removal tool that depresses the locking
tangs (barbs) on the connector terminal and allows the connector to be removed from the rear of the
shell. The connector shell should be replaced if it shows any evidence of burning, melting, cracks, or
breaks. Replace individual terminals that are burnt, corroded, distorted or loose.
Weatherproof connectors are most commonly used in the engine compartment or where the

Test Equipment

Pinpointing the exact cause of trouble in an electrical circuit is most times accomplished by the use of special
test equipment. The following describes different types of commonly used test equipment and briefly explains
how to use them in diagnosis. In addition to the information covered below, the tool manufacturer's
instructions booklet (provided with the tester) should be read and clearly understood before attempting any
test procedures.

JUMPER WIRES

Never use jumper wires made from a thinner gauge wire than the circuit being tested. If the jumper wire is of
too small a gauge, it may overheat and possibly melt. Never use jumpers to bypass high resistance loads in a
circuit. Bypassing resistances, in effect, creates a short circuit. This may, in turn, cause damage and fire.
Jumper wires should only be used to bypass lengths of wire or to simulate switches.
Jumper wires are simple, yet extremely valuable, pieces of test equipment. They are basically test wires which
are used to bypass sections of a circuit. Although jumper wires can be purchased, they are usually fabricated
from lengths of standard automotive wire and whatever type of connector (alligator clip, spade connector or
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HOW TO USE THIS BOOK
connector is exposed to the elements
CAUTION
CONNECTORS