Motor pump
Dump
Suction
(right side of pump) The
pump piston moves to the left and the suction valve opens and brake
fluid is sucked in.
Pressure
increase (left side of pump) The
left piston moves to the left and the pressure valve opens and
pressure is built up.
Suction
Air bleeding in the workshop location
When the ESP hydraulic unit is replaced in the workshop, no special action is required because replacement parts are always delivered prefilled so that the pump circuit need not be bled
HYDRAULIC FLOW
In
this position, the inlet valve and the TCS valve are open, the
outlet valve and the electrically operated shuttle valve remain
closed.In braking position
The
on/off booster builds up a pressure of approximately 10 bar in order
to enable the ESP pump to suck brake fluid at low temperatures. In
this position, the inlet valve is driven in a pulsed cycle. The TCS
valve is closed. The outlet valve remains closed. The electrically
operated shuttle valve is opened. The hydraulic pressure is led to
the wheel brakes which are
to be applied for a brief period of time. .
In esp control (pressure increase)
6. Inputs and outputs
7. Inputs
Active wheel speed sensor (hall ic type)
Type: Hall Effect
Components: HALL IC, Capacitor, Magnet
Output signal: Digital (Open Collector Type circuit integrated)
Good characteristics against temperature variation and noise
Low RPM Detection: 0 RPM can be detected
Air gap sensitivity: stable output pulse width against air-gap change
Supplying power: DC 12V
G
enerated
output current from the sensor is 7mA or 14mA. So in order to check
the sensor function, the output current needs to be check. If the
current measurement is not available, the output
voltage waveform can be checked.
The wheel sensors are constantly checked electrically by the control module. In addition, the sensor signal is checked while the vehicle is running. If there is a malfunction or a non-plausible physically possible signal, ABS and ESP is switched off and the ABS warning lamp and ESP OFF warning lamp is switched on.
Comparison between the passive wheel sensor and the active wheel sensor
YAW RATE SENSOR & LATERAL ACCELERATION SENSOR
Operating Voltage: 5 ±0.25 V
Operating Temperature : - 40 ~ 85 ℃
G-Sensor Range : - 1.5 ~ 1.5 g
Yaw-Sensor Range: - 75 ~ +75 ˚/sec
Zero Output Voltage: 2.5 V
Output Voltage Range: 0.5 ~ 4.5 V
* Driving through a left curve leads to a more positive output signal
H
i-scan
data
