Yamaha WaveRunner VX 700, Service Manual

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7-5
ELEC
Electrical system
– +
Electrical analysis
To measure the peak voltage
When measuring the peak voltage, do not
touch any of the connections of the digital
tester probes.
• When testing the voltage between the
terminals of an electrical component
with the digital tester, do not allow any
of the leads to touch any metal parts.
• When starting the engine on land, make
sure to connect a garden hose to the
watercraft for proper water supply.
To check the electrical components or mea-
sure the peak voltage, use the special ser-
vice tools. A faulty electrical component can
be easily checked by measuring the peak
voltage. The specified engine speed when
measuring the peak voltage is affected by
many factors, such as fouled spark plugs or a
weak battery. If one of these factors is
present, the peak voltage cannot be mea-
sured properly.
TIP:
• Before measuring the peak voltage, check
all wiring for proper connection and corro-
sion, and check that the battery is fully
charged.
• Use the peak voltage adapter with the rec-
ommended digital circuit tester.
• Connect the positive pin of the peak voltage
adapter to the positive terminal of the digital
circuit tester, and the negative pin to the
negative terminal.
• When measuring the peak voltage, set the
selector on the digital circuit tester to the
DC voltage mode .
Ignition system
Ignition coil
Ignition spark
• When performing the spark gap test,
take special care not to let sparks leak
out of the removed spark plug cap.
• When performing the spark gap check,
keep flammable gas or liquids away,
since this test can produce sparks.
1. Connect the spark plug cap to the special
service tool.
2. Crank the engine and observe the igni-
tion spark through the discharge window.
3. Check the ignition spark. WARNING! Do
not touch any of the connections of
the special service tool leads.
4. Measure the CDI unit output peak volt-
age and ignition coil resistance, if there is
no spark, or the spark is weak.
Digital circuit tester
1
: 90890-03174
Peak voltage adapter B
2
: 90890-03172
DC V
1
2
OK