DTC C1702: Variant Coding Error: General Description

IBAU is an integrated ECU consisting of ABS/ESC (ESP), HPU (Hydraulic Power Unit), and BAU (Brake Actuation Unit). HPU consists of a pump motor, a solenoid valve, a high pressure accumulator, and a pressure sensor.

HPU is responsible for increasing/decreasing the hydraulic pressure supplied to the booster and the pedal simulator. ABS/ESC (ESP) consists of a hydraulic pressure supply and a modulator valve block. Hydraulic pressure is decreased/increased by an electric motor, and a control pressure is supplied to the pump in accordance with the signal which is detected by the wheel speed sensor. The hydraulic unit, consisting of an accumulator, a return pump, and a solenoid, activates the return pump using ABS/ESC (ESP) control signals when ABS/ESC (ESP) runs, and controls (increases/decreases/keeps) hydraulic pressure that is applied to individual wheel cylinders.