This warning light illuminates:
If the brake fluid level in the reservoir is low:
1. Drive carefully to the nearest safe location and stop your vehicle.
2. With the engine stopped, check the brake fluid level immediately and add fluid as required (For more details, refer to "Brake Fluid" in chapter 7). After adding brake fluid, check all brake components for fluid leaks. If a brake fluid leak is found, or if the warning light remains on, or if the brakes do not operate properly, do not drive the vehicle. Have the vehicle inspected by an authorized HYUNDAI dealer.
Dual-diagonal braking system
Your vehicle is equipped with dualdiagonal braking systems. This means you still have braking on two wheels even if one of the dual systems should fail.
With only one of the dual systems working, more than normal pedal travel and greater pedal pressure is required to stop the vehicle.
Also, the vehicle will not stop in as short a distance with only a portion of the brake system working.
If the brakes fail while you are driving, shift to a lower gear for additional engine braking and stop the vehicle as soon as it is safe to do so.
WARNING
Parking Brake & Brake Fluid Warning Light
Driving the vehicle with a warning light ON is dangerous. If the Parking Brake & Brake Fluid Warning Light illuminates with the parking brake released, it indicates that the brake fluid level is low.
In this case, have your vehicle inspected by an authorized HYUNDAI dealer.
Hyundai Elantra AD (2016-2020) Service Manual: Master Cylinder Components and Components Location
Components
1.Reservoir cap2. Reservoir3.Reservoir4. Grommet5. Master cylinder
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Hyundai Elantra AD (2016-2020) Service Manual: Rear Seat Assembly Components and Components Location
Component Location
1. Rear seat cushion assembly2. Rear seat back assembly
...