Chrysler 1998 Voyager Service Manual page 571

NS/GS
DIAGNOSIS AND TESTING (Continued)
• Voltmeter - Used to check for voltage on a cir-
cuit. Always connect the black lead to a known good
ground and the red lead to the positive side of the
circuit.
CAUTION: Most of the electrical components used
in today's vehicle are solid state. When checking
voltages in these circuits use a meter with a 10-me-
gohm or greater impedance rating.
• Ohmmeter - Used to check the resistance
between two points of a circuit. Low or no resistance
in a circuit means good continuity.
CAUTION: - Most of the electrical components used
in today's vehicle are Solid State. When checking
resistance in these circuits use a meter with a 10-
megohm or greater impedance rating. In addition,
make sure the power is disconnected from the cir-
cuit. Circuits that are powered up by the vehicle
electrical system can cause damage to the equip-
ment and provide false readings.
• Probing Tools - These tools are used for probing
terminals in connectors (Fig. 6). Select the proper
size tool from Special Tool Package 6807, and insert
it into the terminal being tested. Use the other end
of the tool to insert the meter probe.
Fig. 6 Probing Tool
INTERMITTENT AND POOR CONNECTIONS
Most intermittent electrical problems are caused
by faulty electrical connections or wiring. It is also
possible for a sticking component or relay to cause a
problem. Before condemning a component or wiring
assembly check the following items.
• Connectors are fully seated
• Spread terminals, or terminal push out
• Terminals in the wiring assembly are fully
seated into the connector/component and locked in
position
• Dirt or corrosion on the terminals. Any amount
of corrosion or dirt could cause an intermittent prob-
lem
• Damaged connector/component casing exposing
the item to dirt and moisture
8W-01 GENERAL INFORMATION
a short to ground
of the insulation covering.
TROUBLESHOOTING TESTS
system use the Wiring Diagrams and study the cir-
cuit. Also refer to the Troubleshooting Wiring Prob-
lems in this section.
TESTING FOR VOLTAGE POTENTIAL
known good ground (Fig. 7).
selected test point. The vehicle ignition may need to
be turned ON to check voltage. Refer to the appropri-
ate test procedure.
TESTING FOR CONTINUITY
or, disconnect the battery.
of the circuit being tested (Fig. 8).
circuit being tested. Low or no resistance means good
continuity.
TESTING FOR A SHORT TO GROUND
involved with the fuse.
terminals of the fuse.
• Wire insulation that has rubbed through causing
• Some or all of the wiring strands broken inside
• Wiring broken inside of the insulation
Before beginning any tests on a vehicles electrical
(1) Connect the ground lead of a voltmeter to a
(2) Connect the other lead of the voltmeter to the
Fig. 7 Testing for Voltage Potential
(1) Remove the fuse for the circuit being checked
(2) Connect one lead of the ohmmeter to one side
(3) Connect the other lead to the other end of the
(1) Remove the fuse and disconnect all items
(2) Connect a test light or a voltmeter across the
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