Checking The Electrical Component; Using The Ydis; Measuring The Peak Voltage - Yamaha F150A Service Manual

Checking the electrical
component

Using the YDIS

When checking the TPS, ISC valve, high-
pressure fuel pump, fuel injector, or each
sensor, use the YDIS.
TIP:
• When deleting the diagnosis record in the
YDIS, make sure to check the time that the
trouble codes were detected.
• When checking the input voltage of a part,
the coupler or connector must be discon-
nected. As a result, the engine ECM deter-
mines that the part is disconnected and a
trouble code is detected. Therefore, make
sure to delete the diagnosis record after
checking the input voltage.
• To connect and operate the YDIS, see the
YDIS (Ver. 2.00 or later) instruction manual.

Measuring the peak voltage

When measuring the peak voltage, do not
touch any of the connections of the digital
tester probes.
When measuring
between the terminals of an electrical
component using the digital tester, make
sure that the leads do not contact any
metal parts. Otherwise, the electrical com-
ponent may short-circuit and be dam-
aged.
To check the electrical components or mea-
sure the peak voltage, use the special ser-
vice tools. A malfunctioning
component can be checked easily by mea-
suring 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
measured properly.
the peak voltage
electrical

Checking the electrical component

TIP:
• Before measuring the peak voltage, check
all of the wiring harnesses for corrosion.
Also, make sure that the wiring harnesses
are connected properly and that the battery
is fully charged.
• Use peak voltage adapter B with the rec-
ommended digital circuit tester.
• Connect the positive pin of peak voltage
adapter B to the positive terminal of the dig-
ital tester, and connect the negative pin to
the negative terminal.
• When measuring the peak voltage, set the
digital circuit tester to the DC voltage mode.
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.
DC V
Digital circuit tester: 90890-03189
Peak voltage adapter B: 90890-03172
5-12
0
1
2
3
4
5
6
7
8
9
10
A