Basic Electrical Diagnostic Methods; Voltage Measurement; How To Measure Voltage Using A Voltmeter - Honda Motorcycle Service Manual

ELECTRICAL FUNDAMENTALS
BASIC ELECTRICAL DIAGNOSTIC
METHODS
VOLTAGE MEASUREMENT
VOLTMETER
-
-
-
-
-
-
Measuring voltage is a fundamental method of checking circuit
components. The measurement is conducted for the following
reasons.
a
To check if voltage exists. (A test light may also be used.)
@
To measure the actual value.
A voltmeter is used t o determine if an electrical component
is operating normally.
HOW TO MEASURE VOLTAGE USING A
VOLTMETER
- -
is clean and free of paint.
Use a bolt attached directly to the frame.
Select the current range to measure the expected voltage
value. If the voltage value is unknown; start at the highest
scale on the meter and go to lower scales as necessary t o
obtain an accurate reading. Apply the red probe to the positive
end and the black probe to the negative end of the circuit. The
diagram on the right shows that the voltmeter registers the
voltage across the light bulb. Voltmeters are always connected
in parallel, not in series.
CONNECTED IN PARALLEL
CONNECTED IN SERIES
(GOOD)
I
(NOGOOD)
1. If both light bulbs B and C not working and there is no
voltage at bulb B and C with the ignition switch ON. chick
voltage at
a.
2. If no voltage is measured at
O,
check voltage at
O
in case
of a bad connection at connector A. If voltage exists at
@ z )
and not at
a,
there is problem at connector A.
Example 1
First study the circuit diagram.
If light bulbs B and C do not work, and A is OK, check for
voltage at bulbs Band C. If there is voltage, the problem is in
the ground side of the circuit. If no voltatge is found. the
problem is on the "hot
"
side of the circuit.
If voltage registers at both
O
and
Q?,
switch A should be
checked.
WIRE HARNESS
IGNITION SWITCH
-
. .
-
Date of Issue
:
March, 1995
21-14
o
HONDA MOTOR CO.,LTD.