Hydraulic Unit Operation Test - Yamaha YZF-R1 2020 Service Manual

TIP
There is an identifying white paint mark "c" on
the upper surface of the pipe of the brake hose
(front brake master cylinder to the hydraulic
unit).
b
1
6. Connect:
• ABS ECU coupler "1"
TIP
Connect the ABS ECU coupler, and then push
the lock lever of the coupler in the direction of the
arrow shown.
1
7. Fill:
• Brake fluid reservoir
(with the specified amount of the specified
brake fluid)
Specified brake fluid
DOT 4
EWA17280
WARNING
• Use only the designated brake fluid. Other
brake fluids may cause the rubber seals to
deteriorate, causing leakage and poor
brake performance.
• Refill with the same type of brake fluid that
is already in the system. Mixing brake fluids
may result in a harmful chemical reaction,
leading to poor brake performance.
a
c
4-79
ABS (Anti-lock Brake System)
• When refilling, be careful that water does
not enter the brake master cylinder reser-
voir or brake fluid reservoir. Water will sig-
nificantly lower the boiling point of the
brake fluid and could cause vapor lock.
ECA13540
NOTICE
Brake fluid may damage painted surfaces
and plastic parts. Therefore, always clean up
any spilt brake fluid immediately.
8. Bleed:
• Brake system
Refer to "BLEEDING THE HYDRAULIC
BRAKE SYSTEM (ABS)" on page 3-16.
9. Check the operation of the hydraulic unit ac-
cording to the brake lever and the brake ped-
al response. (Refer to "HYDRAULIC UNIT
OPERATION TEST" on page 4-79.)
ECA14770
NOTICE
Always check the operation of the hydraulic
unit according to the brake lever and the
brake pedal response.
10.Delete the DTC. (Refer to "SELF-DIAGNOS-
TIC FUNCTION AND DIAGNOSTIC CODE
TABLE" on page 9-40.)
11.Perform a trial run. (Refer to "CHECKING
THE ABS WARNING LIGHT" on page 4-82.)
EAS30201

HYDRAULIC UNIT OPERATION TEST

The reaction-force pulsating action generated in
the brake lever and brake pedal when the ABS
is activated can be tested when the vehicle is
stopped.
The hydraulic unit operation can be tested using
the following two methods.
• Brake line routing confirmation: this test
checks the function of the ABS after the sys-
tem was disassembled, adjusted, or serviced.
• ABS reaction-force confirmation: this test gen-
erates the same reaction-force pulsating action
that is generated in the brake lever and brake
pedal when the ABS is activated.
Brake line routing confirmation
EWA13120
WARNING
Securely support the vehicle so that there is
no danger of it falling over.