Yamaha MTN850-A 2017 Service Manual page 491

• Vehicle possibly ridden on uneven roads.
Fault code No. 14, 27
Fault code No.
Item
Symptom
Order Item/components and probable cause
1 Foreign material adhered around the rear
wheel sensor
2 Incorrect installation of the rear wheel
3 Defective sensor rotor or incorrect instal-
lation of the rotor
4 Defective rear wheel sensor or incorrect
installation of the sensor
TIP
• If the rear brake ABS operates continuously for 20 seconds or more, fault code No. 27 will be record-
ed. If the rear brake ABS operates continuously for 36 seconds or more, fault code No. 14 will be re-
corded.
• Vehicle possibly ridden on uneven roads.
Fault code No. 15
Fault code No.
Item
Symptom
Order Item/components and probable cause
1 Defective coupler between the front wheel
sensor and the hydraulic unit assembly
ABS (ANTI-LOCK BRAKE SYSTEM)
14
27
Rear wheel sensor (abnormal pulse period)
Rear wheel sensor signal is not received properly. (The pulse period
is abnormal while the vehicle is traveling.)
Check or maintenance job
Check the surface of the sensor rotor and wheel sensor
for foreign material, such as metal particles.
Clean the sensor rotor and wheel sensor if necessary.
Check the components for looseness, distortion, and
bends.
Refer to "CHECKING THE REAR WHEEL" on page
4-21.
Check the surface of the sensor rotor for damage.
Replace the sensor rotor if there is visible damage.
Refer to "MAINTENANCE OF THE REAR WHEEL
SENSOR AND SENSOR ROTOR" on page 4-22.
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 REAR WHEEL
SENSOR AND SENSOR ROTOR" on page 4-22.
15
Front wheel sensor (open or short circuit)
Open or short circuit is detected in the front wheel sensor.
Check or maintenance job
• 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.
TIP
Turn the main switch to "OFF" before disconnecting or
connecting a coupler.
8-134