Troubleshooting - Yamaha XP500 Service Manual

TROUBLESHOOTING

EAS00881
ABS troubleshooting outline
Use this section to troubleshoot the ABS. Read this service manual carefully and make sure you
understand the information provided before repairing any malfunctions or performing service.
The electronic control unit (ECU) has an ABS self-diagnostic function. When failures occur in the
ABS, the ABS warning light on the meter assembly indicates a malfunction.
The troubleshooting below describes the problem identification and service method according to the
indications by the multifunction display. For troubleshooting other than the following items, follow
the normal service method.
WARNING
_
When maintenance or checks have been performed on components related to the ABS, be
sure to perform a final check before delivering the vehicle to the customer. (Refer to "[D-6]
Final check".)
1. ABS condition when the ABS warning light comes on
1) ABS warning light remains on. → The ABS is not operating, manual braking is used.
• Diagnose the malfunction using the ABS self-diagnostic function.
2) Light comes on, and then goes off when starting → ABS operation is normal.
• The ABS warning light comes on for 2 seconds, and then goes off every time the main switch is
set to "ON".
3) ABS warning light flashes. → ABS operation is normal.
• The brake switch is defective or improperly adjusted.
• The rear wheel is racing.
• The vehicle is continuously ridden on extremely uneven roads.
2. Self-diagnosis and service
The ECU (ABS) has an ABS self-diagnostic function. By utilizing this function, quick problem
identification and service are possible. The malfunction codes are stored in the memory of the
ECU (ABS).
Malfunctions are detected
The ABS warning light cannot be used to recall the malfunction codes from the memory of the ECU
(ABS) if the ABS warning light is already on. Connect the test coupler adaptor to the test coupler,
connect a pocket tester to the terminal of the light green lead of the test coupler adaptor, and deter-
mine the malfunction codes by the movement of the pocket tester needle. (Refer to "[B-5] ABS mal-
function check using the ABS self-diagnosis (present malfunction)".)
Malfunctions are not detected
The multifunction display indicates all the malfunction codes recorded in the ECU (ABS).
You can also recall the malfunction codes by using a pocket tester. Note all malfunction codes if
more than two malfunction codes are stored in the memory.
Deleting the malfunction codes
When the service has been completed, check the normal operation of vehicle and then delete the
malfunction codes. (Refer to "[D-6] Final check".) By deleting the malfunction code memory, it is
possible to pursue the cause correctly if the next malfunction occurs.
ANTI-LOCK BRAKE SYSTEM (XP500A)
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CHAS