Fig. 14.1. Measuring the height of the brake pedal position (nominal value 163.5–166.5 mm): 1 – brake light switch; 2 – pusher lock nut; 3 – pusher
Measure the pedal height as shown in Fig. 14.1. If the measured height does not correspond to the nominal value, perform the following operations.
1. Disconnect the connector from the brake light switch.
Fig. 14.2. Adjusting the height of the brake pedal above the floor for vehicles with ABS: 1 – lock nut
2. Loosen the pusher lock nut and, by turning the pusher in one direction or another, use pliers to adjust the required height of the brake pedal above the floor (for vehicles with ABS) (Fig. 14.2).
3. Tighten the pushrod lock nut (for vehicles with ABS).
4. Move the brake light switch in the direction of the brake pedal travel until it stops. The switch will only move when pressed firmly.
Fig. 14.3. Measuring the installation gap of the brake light switch
5. Raise the brake pedal until the plunger is fully extended, and then move the brake light switch to the desired position. Rotate the switch to adjust its position so that the gap corresponds to that shown in Fig. 14.3.
6. Connect the brake light switch connector.
7. Make sure that the brake lights do not come on when the brake pedal is released.
8. With the engine not running, press the brake pedal two or three times.
9. After removing the vacuum from the brake booster, press the brake pedal by hand and make sure that the pedal travel before resistance begins (free play) is in the optimal range.
10. If the free play of the brake pedal exceeds the nominal value, then the gap in the connection of the brake pedal lever to the pedal mounting bracket is probably increased. Check the gap and replace damaged parts if necessary. The nominal value is 3-8 mm
11. Start the engine, press the brake pedal with a force of approximately 490 N and measure the distance between the floor of the passenger compartment and the pedal. The nominal value is more than 80 mm.
12. If this distance is less than the standard value, check for air in the brake hydraulic system, clearance between the shoes and drum of drum brakes, or parking brake drag. Adjust and replace faulty parts if necessary.