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ELECTRONIC STABILITY PROGRAM (ESP)
7
1.3 COMPONENTS
NOTE
For all components except ESP ECU, Steering angle sensor and ESP warning lamp refer ABS section.
A. ESP ECU AND HYDRAULIC UNIT
The ESP ECU and hydraulic control unit consist of a hydraulic modulator with integrated pressure sensor
and electronic control unit. 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.
The HCU of ABS vehicles (ABS only) and ESP vehicles cannot be interchanged. ESP hydraulic unit have
additional 4 valves for Brake pressure increase.