Yamaha MT-09 2021, Service Manual

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9-45
ABS (Anti-lock Brake System)
EAS32897
[A] CHECKING THE ABS WARNING LIGHT
Turn the main switch to “ON”. (Do not start the engine.)
1. The ABS warning light does not come on.
• Only the ABS warning light fails to come on. [A-1]
• The ABS warning light and all other indicator lights fail to come on. [A-2]
2. The ABS warning light comes on. [A-3]
EAS32898
[A-1] ONLY THE ABS WARNING LIGHT FAILS TO COME ON
1. Check for a short circuit to the ground between the green/orange terminal of the ABS ECU coupler
and green/orange terminal of the meter assembly.
• If there is short circuit to the ground, the wire harness is defective. Replace the wire harness.
2. Disconnect the ABS ECU coupler and check that the ABS warning light comes on when the main
switch is turned to “ON”.
• If the ABS warning light does not come on, the meter assembly circuit (including the ABS warning
light [LED]) is defective. Replace the meter assembly.
• If the ABS warning light comes on, the ABS ECU is defective. Replace the hydraulic unit assembly.
EAS32899
[A-2] ALL INDICATOR LIGHTS FAIL TO COME ON
1. Main switch
• Check the main switch for continuity.
Refer to “CHECKING THE SWITCHES” on page 8-53.
• If there is no continuity, replace the main switch/immobilizer unit.
2. Battery
• Check the condition of the battery.
Refer to “CHECKING AND CHARGING THE BATTERY” on page 8-56.
• If the battery is defective, clean the battery terminals and recharge it, or replace the battery.
3. Main fuse
• Check the fuse for continuity.
Refer to “CHECKING THE FUSES” on page 8-55.
• If the main fuse is blown, replace the fuse.
4. Circuit
• Check the meter assembly circuit.
Refer to “CIRCUIT DIAGRAM” on page 9-36.
• If the meter assembly circuit is open, replace the wire harness.
EAS32900
[A- 3 ] THE ABS WARNING LIGHT COMES ON
Connect the YDT to the YDT coupler and execute functional diagnosis. (For information about how to
execute functional diagnosis, refer to the operation manual that is included with the tool.)
Check that communication with the ABS ECU is possible.
• Only the ABS ECU fails to communicate. [A-4]
• ABS ECU and FI ECU fail to communicate. [A-5]
• Communication is possible with the ABS ECU. [B-1] (The ABS is displayed on the select unit screen.)
EAS32901
[A-4] ONLY THE ABS ECU FAILS TO COMMUNICATE
1. ABS ECU fuse
• Check the ABS ECU fuse for continuity.
Refer to “CHECKING THE FUSES” on page 8-55.
• If the ABS ECU fuse is blown, replace the fuse.