Yamaha R15 2022 Service Manual page 459

Fault code No.
Item
Symptom
Order Item/components and probable cause
4 Defective rear wheel sensor or incorrect
installation of the sensor
Fault code No. 21
Fault code No.
Item
Symptom
Order Item/components and probable cause
1 Defective hydraulic unit assembly
Fault code No. 24
Fault code No.
Item
Symptom
Order Item/components and probable cause
1 Defective signaling system (tail/brake
light or brake light switch)
2 Defective coupler between the signaling
system (tail/brake light or brake light
switch) and the hydraulic unit assembly
3 Open or short circuit in the wire harness
between the signaling system (tail/brake
light or brake light switch) and the hydrau-
lic unit assembly
4 Defective hydraulic unit assembly
ABS (ANTI-LOCK BRAKE SYSTEM)
18
46
Rear wheel sensor (missing pulses)
Rear wheel sensor signal is not received properly. (Missing pulses
are detected in the signal while the vehicle is traveling.)
21
Hydraulic unit assembly (defective solenoid drive circuit)
Solenoid drive circuit in the hydraulic unit assembly is opened or
short-circuited.
24
Brake light switch or tail/brake light
Brake light signal is not received properly while the vehicle is travel-
ing (Brake light circuit, or front or rear brake light switch circuit).
Check or maintenance job
Check the wheel sensor for damage and the installed
condition of the sensor. Repair or replace the wheel
sensor if necessary.
Refer to "MAINTENANCE OF THE WHEEL SENSOR
AND SENSOR ROTOR" on page 4-16.
Check or maintenance job
Replace the hydraulic unit assembly.
Refer to "ABS (ANTI-LOCK BRAKE SYSTEM)" on page
8-101.
Check or maintenance job
Check the brake light switches.
Refer to "CHECKING THE SWITCHES" on page 8-139.
• Check the coupler for any pins that may be pulled out.
• Check the locking condition of the coupler.
• If there is a malfunction, repair it and connect the cou-
pler securely.
• Between ABS ECU coupler and front brake light
switch coupler.
(gray–gray)
• Between ABS ECU coupler and rear brake light switch
coupler.
(gray–gray)
If the above items were performed and no malfunctions
were found, replace the hydraulic unit assembly.
Refer to "ABS (ANTI-LOCK BRAKE SYSTEM)" on page
8-101.
8-126
ELEC – +