Since the drive axle and MG2 are always joined mechanically When the vehicle

Since the drive axle and mg2 are always joined

This preview shows page 179 - 182 out of 184 pages.

Since the drive axle and MG2 are always joined mechanically: When the vehicle decelerates, the drive wheels turn MG2 and the hybrid system uses it as a generator (on 4WD hybrid SUVs, MGR is also used as a generator during regenerative braking). When MG2 is controlled as a generator, it resists the rotation of the drive wheels, providing the brake force to slow the vehicle. The greater the generated amperage (battery charging amperage), the greater is the resistance force. The apportioning of the brake force between the hydraulic brake and the regenerative brake varies by brake force and time to match the driver’s demand. During heavy braking, the hydraulic brakes do most of the work. During moderate braking, regeneration provides most of the brake force. Hydraulic brakes hold the vehicle in place when stopped.
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553 Brake Systems Technician Handbook Brake Pedal Stroke Sensor SERVICE TIP 172 Technical Training The brake pedal stroke sensor contains a contact variable resistor. The sensor detects the extent of the brake pedal stroke and sends this information to the Skid Control ECU. Note the following precautions when installing a brake pedal stroke sensor (available as a service part): Initially, the sensor lever is locked into the 0 stroke position by a small pin. Do not detach the pin until the installation has been completed. Install the sensor with the brake pedal completely released. After installation, firmly press the brake pedal once to break off the pin. Make sure the broken pin does not remain in the sensor lever. While the battery is connected, even if the power switch is off, the brake control system activates when the brake pedal is depressed or any door courtesy switch turns on. Therefore, when servicing the brake system components, do not operate the brake pedal or open or close the doors while the battery is connected.
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553 Brake Systems Technician Handbook The stroke simulator generates a pedal stroke equivalent to the amount of brake pedal application from the driver during brake operation. With a brake system malfunction, the Switching Solenoid Valve (SSC) is closed and the fluid flow is shut off from the master cylinder. The stroke simulator is located between the master cylinder and the brake actuator. It uses 2 coil springs with different spring constants to provide different pedal stroke characteristics. Note : If the brake pedal is depressed before the brake control system is prepared to operate, the pedal stroke may seem unusually long or short as the cut solenoid has not yet operated. This is not a system malfunction. During regenerative braking, fluid flow to the front calipers is limited. The stroke simulator consumes some of the fluid flow from the master cylinder so that the pedal can move normally. This makes the pedal stroke feel the same to the driver, whether regenerative braking, hydraulic braking, or a combination is employed. The stroke simulator solenoid generates pedal reactive effort during Electronically Controlled Brake operation. If 1 of the 4 wheels loses brake booster function stroke simulator operation is prohibited.
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  • Fall '08
  • Huie,B
  • Brake, Disc brake, Drum brake, Vehicle braking technologies, Brake Systems, disc brakes

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