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ELECTRONIC STABILITY PROGRAM (ESP)
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D
SYSTEM LAYOUT
The hydraulic circuit layout of the ESP system in this TATA vehicle is similar to ABS, i.e., vertical split. For
details refer the Hydraulic System Layout in ABS Section.
The ESP system consists of a hydraulic modulator with integrated pressure sensor, electronic control unit
and four-wheel speed sensors, which it shares with the ABS system. In addition to the individual wheel
valves present for the ABS the ESP hydraulic modulator has a pair of internal switching valves on the
primary and secondary brake circuits from the master cylinder. These are used when brake pressure has to
be increased at individual wheels. It has a Integrated yaw rate sensor and steering angle sensor connected
via the high speed CAN, which is also used to connect the ESP to the Instrument cluster, engine and PEPS
ECU. There is 1 additional information lamp in the instrument cluster which is used to identify when the
system is operating and when a fault has been detected.