Hydraulic Control Valve - Yamaha 2012 TMAX XP500A Service Manual

• Hydraulic control valve

The hydraulic control valve is composed of a inlet solenoid valve and outlet solenoid valve.
The electromagnetic force generated in the inlet solenoid valve varies proportionally with the duty
cycle control voltage that is supplied to it. Since this voltage is continuously variable, the solenoid
valve moves smoothly and the hydraulic pressure is adjusted linearly.
1. When the brakes are operated normally, the inlet solenoid valve "1" is open and the outlet sole-
noid valve "2" is closed. The brake line between the brake master cylinder and brake caliper is
open.
2. When the ABS is activated, the inlet solenoid valve "1" closes and the outlet solenoid valve "2"
opens using the power supplied from the ABS ECU signals. This reduces the hydraulic pres-
sure.
3. When the ABS ECU sends a signal to stop reducing the hydraulic pressure, the outlet solenoid
valve "2" closes and the brake fluid is pressurized again. The inlet solenoid valve "1" controls
the hydraulic pressure difference between the brake fluid in the upper brake lines (brake mas-
ter cylinder side) and the brake fluid in the lower brake lines (brake caliper side).
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FEATURES