Speed Sensor; Knock Sensor - Yamaha PZ50W Service Manual

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SIGNAL SYSTEM

SPEED SENSOR

1. Inspect:
• Speed sensor
Inspection steps:
• Connect the pocket tester (DC 20 V) to the
speed sensor coupler (wire harness side) as
shown.
Positive tester probe → White/Yellow
Negative tester probe → Black/Blue
Positive battery terminal → Blue
Negative battery terminal → Black/Blue
• Elevate the track and slowly rotate it.
• Measure the voltage (DC 5 V) of white/yellow
and black/blue. With each full rotation of the
track the voltage reading should cycle from 0.6
V to 4.8 V to 0.6 V to 4.8 V.
Out of specification → Replace.

KNOCK SENSOR

1. Remove:
• Knock sensor
CAUTION:
Handle the knock sensor with special care.
Never subject it to shock or allow it to be
dropped. If it is dropped, it must be replaced.
2. Connect:
• Pocket tester
(to the knock sensor coupler and sensor
body)
3. Measure:
• Knock sensor resistance
Out of specification → Replace.
Knock sensor resistance:
504 ~ 616 kΩ at 20 °C (68 °F)
4. Install the knock sensor and connect the knock
sensor coupler.
Knock sensor:
27 Nm (2.7 m · kg, 19 ft · lb)
CAUTION:
Do not overtighten the knock sensor.
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