Yamaha YZF-R1P Service Manual page 365

Fault code No. 42
Used diagnostic code No. 07 (speed sensor)
No. 21 (neutral switch)
Inspection operation item and probable cause Operation item and countermeasure
Defective speed sensor
Open or short circuit in speed sensor lead.
Gear for detecting vehicle speed has broken. Replace if defective.
Connected condition of speed sensor connec-
tor
Inspect the coupler for any pins that may have
pulled out.
Check the locking condition of the coupler.
Defective neutral switch
Faulty shift drum
(neutral detection area)
Open or short circuit in neutral switch lead.
Connected condition of connector
Inspect the coupler for any pins that may have
pulled out.
Check the locking condition of the coupler.
FUEL INJECTION SYSTEM
Symptom 1 No normal signals are received from the speed sensor.
2 Open or short circuit is detected in the neutral switch.
Replace if defective.
1. Measure the speed sensor output voltage.
2. Connect the pocket tester (DC 20 V) to the
speed sensor coupler terminal as shown.
Tester positive probe → pink 1
Tester negative probe → black/white 2
3. Measure the speed sensor output voltage.
4. Is the speed sensor OK?
Repair or replace if there is an open or short
circuit.
Between sensor coupler and ECU coupler.
Blue - Blue
White/Yellow - White/Yellow
Black/Blue - Black/Blue
Refer to "TRANSMISSION" in chapter 5.
If there is a malfunction, repair it and connect it
securely.
Speed sensor coupler
Main wiring harness ECU coupler
Replace if defective.
Refer to "CHECKING THE SWITCHES" in
chapter 8.
Replace if defective.
Refer to "TRANSMISSION" in chapter 5.
Repair or replace if there is an open or short
circuit.
Between switch connector and ECU coupler
Sky blue - Black/Yellow
If there is a malfunction, repair it and connect it
securely.
Neutral switch connector
Main wiring harness ECU coupler
7 - 24
Speed sensor output voltage
When sensor is on
DC 4.8 V or more
When sensor is off
DC 0.6 V or less
FI
Reinstatement
method
Reinstated by
starting the engine,
and inputting the
vehicle speed sig-
nals by operating
the motorcycle at a
low speed of 20 to
30 km/h. (12 to
19 mi/h)