Final answer:
The correct answer to the ECB system question is option 'SLC and SLR'. These solenoids confine the fluid within the master cylinder and engage the stroke simulator when the brake pedal is applied.
Step-by-step explanation:
The correct answer is option SLC and SLR. In an Electronically Controlled Brake (ECB) system without power source backup, during brake pedal application, two solenoids are specifically used to confine the fluid within the master cylinder and to engage the stroke simulator.
These solenoids are SLC (Solenoid Control Left) and SLR (Solenoid Control Right). The SLC and SLR solenoids work in tandem to maintain the hydraulic pressure necessary for consistent brake pedal feel and effective brake actuation in the absence of an external power source.
Functionally, when the brake pedal is pressed, the SLC and SLR solenoids close to seal off the master cylinder from the rest of the hydraulic circuit. This allows the master cylinder to build up pressure on the brake pedal apply, which is then transmitted to the stroke simulator.
The stroke simulator provides the driver with the necessary pedal feel by simulating the resistance that would typically be provided by the hydraulic pressure in a traditional brake system.
In an ECB system without power source backup, the solenoids that close to confine the fluid within the master cylinder and stroke simulator on the brake pedal are the SMC (Stroke Master Control) solenoid and the SRC (Stroke Rear Control) solenoid.
These solenoids play a crucial role in controlling the flow of hydraulic fluid and maintaining the desired pressure within the system.