Yamaha YZF-R1 2020 Service Manual page 526

2. ABS ECU coupler
• Check that the ABS ECU coupler is connected properly.
For information about connecting the ABS ECU coupler properly, refer to "INSTALLING THE HY-
DRAULIC UNIT ASSEMBLY" on page 4-78.
3. Wire harness
• Open circuit between the main switch and the ABS ECU, or between the ABS ECU and the ground.
Check for continuity between brown/blue terminal of the main switch coupler and red/black terminal
of the ABS ECU coupler.
Check for continuity between black terminal of the ABS ECU coupler and the ground.
If there is no continuity, the wire harness is defective. Replace the wire harness.
• Open circuit in the wire harness between the ABS ECU coupler and the YDT coupler.
Check for continuity between blue/white terminal of the ABS ECU coupler and blue/white terminal
of the YDT coupler. (CANH)
Check for continuity between blue/black terminal of the ABS ECU coupler and blue/black terminal
of the YDT coupler. (CANL)
4. ABS ECU malfunction
Replace the hydraulic unit assembly.
EAS32902
[A-5] ABS ECU AND FI ECU FAIL TO COMMUNICATE
1. YDT
Check that the YDT is properly connected.
2. Wire harness
• Open circuit in the wire harness between the ABS ECU coupler and the YDT coupler.
Check for continuity between blue/white terminal of the ABS ECU coupler and blue/white terminal
of the YDT coupler. (CANH)
Check for continuity between blue/black terminal of the ABS ECU coupler and blue/black terminal
of the YDT coupler. (CANL)
EAS32903
[B-1] MALFUNCTION ARE CURRENTLY DETECTED
When the YDT is connected to the YDT coupler, the DTC will be displayed on the computer screen.
• A DTC is displayed. [B-2]
• A DTC is not displayed. [C-1]
EAS32904
[B-2] DIAGNOSIS USING THE DTC
This model uses the YDT to identify malfunctions.
For information about using the YDT, refer to the operation manual that is included with the tool.
Yamaha diagnostic tool USB
90890-03267
Yamaha diagnostic tool (A/I)
90890-03264
TIP
• Yamaha diagnostic tool (A/I) (90890-03264) includes YDT sub harness (6P) (90890-03266).
• If you already have Yamaha diagnostic tool (A/I) (90890-03262), YDT sub harness (6P) (90890-
03266) is separately required.
Details about the displayed DTCs are shown in the following chart. Refer to this chart and check the
vehicle.
Once all the work is complete, delete the DTCs. [B-3]
TIP
Do the final check after terminating the connection with the YDT and turning the main switch off. [C-1]
ABS (Anti-lock Brake System)
9-31