Two
basic tools are essential for trouble shooting electrical problems - a
wiring diagram, and a 12 volt test light. A test light is an
inexpensive little tool that looks like a cross between an ice pick and
an electric screwdriver. Simple to use, it is connected by its clip to
a ground. The sharp probe is poked around the "hot" leads. If the lamp
lights, there's power, at least to that part of the circuit. For
example, clip the test light to a bumper bolt or other good ground and
touch the probe to a bulb contact on the "hot" side - the bulb will
light, (so long as the light is "on").
Most lamp problems are
conveniently found in the lamp unit itself. The great majority are
caused by bad bulb contacts or corroded grounds. Don't assume that
there are major problems until the non-functioning unit is completely
inspected. Using the wiring diagram, work your way back through the
circuit to the connectors, and from there to the source of power such
as the fuse box or terminal connector. By this method, you should be
able to determine whether an entire circuit or the individual unit is
at fault. If the circuit is dead, track the problem from the fuse box
or battery side of that particular circuit. Proceed through the circuit
components one at a time, using the wiring diagram as a guide. Don't
panic!
After reading both these articles, you should be well on your way to trouble-shooting Lucas electrics.
Working on automobiles is inherently dangerous. Moss Motors, Ltd. is not liable for injury or damage due to incorrect installation or use of their products. All products are sold with the understanding that the safe and proper installation and use of the products is the customer’s responsibility. Follow factory workshop manual procedures and instructions, but use current shop safety standards and common sense. Some tasks will require professional advice or services which Moss Motors cannot provide.Email (for Moss Tech help):
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