Component | Procedure |
Brake Booster (A) | Check brake operation by applying the brakes during a test drive. If the brakes do not work properly, check the brake booster. Replace the brake booster as an assembly if it does not work properly or if there are signs of leakage. |
Piston cup and pressure cup inspection (B) | ● Check brake operation by applying the brakes. Look for damage or signs of fluid leakage. Replace the master cylinder as an assembly if the pedal does not work properly or if there is damage or signs of fluid leakage. ● Check for a difference in brake pedal stroke between quick and slow brake applications. Replace the master cylinder if there is a difference in pedal stroke. |
Brake hoses (C) | Look for damage or signs of fluid leakage. Replace the brake hose with a new one if it is damaged or leaking. |
Caliper piston seal and piston boots (D) | Check brake operation by applying the brakes. Look for damage or signs of fluid leakage. If the pedal does not work properly, the brakes drag, or there is damage or signs of fluid leakage, disassemble and inspect the brake caliper. Replace the boots and seals with new ones whenever thebrake caliper is disassembled. |
For simple checking of the brake booster operation, carry out the following tests
Run the engine for one or two minutes, and then stop it. If the pedal depresses fully the first time but gradually becomes higher when depressed succeeding times, the booster is operating properly, if the pedal height remains unchanged, thebooster is defective.
With the engine stopped, step on the brake pedal several times.
Then step on the brake pedal and start the engine. If the pedal moves downward slightly, the booster is in good condition. If there is no change, the booster is defective.
With the engine running, step on the brake pedal and then stop the engine.
Hold the pedal depressed for 30 seconds. If the pedal height does not change, the booster is in good condition, if the pedal rises, the booster is defective.
If the above three tests are okay, the booster performance can be determined as good.
Even if one of the above three tests is not okay, check the check valve, vacuum hose and booster for defect.
Disconnect the brake booster vacuum hose (check valve built in) (A) at the booster (B).
Start the engine and let it idle. There should be vacuum available. If no vacuum is available, the check valve is not working properly. Replace the brake booster vacuum hose and check valve and retest.
PEDAL HEIGHET
Disconnect the brake switch connector, loosen the brake switch locknut (A), and brake off the brake switch (B) until it is no longer touching the brake pedal.
Lift up the carpet. At the insulator cutout, measure the pedal height (C) from the middle of the left-side center of the pedal pad (D).
Standard pedal height( with carpet removed): 184.5mm(7.26 in.)
Loosen the pushrod locknut (A), and screw the pushrod in or out with pliers until the standard pedal height from the floor is reached. After adjustment, tighten the locknut firmly. Do not adjust the pedal height with the pushrod depressed.
Screw in the brake switch until its plunger is fully depressed (threded end (A) touching the pad (B) on the pedal arm) then brake off the switch 3/4 turn to make 1 ~ 2 mm (0.04 ~ 0.08 in.) of clearance between the brake switch connector. Make sure that the brake lights go off when the pedal is released.
With the engine off, inspect the pedal free play (A) on the pedal pad (B) by pushing the pedal by hand.
Free play: 3 ~ 8 mm (0.12 ~ 0.31 in.)
If the pedal free play is out of specification, adjust the brake switch (C). If the pedal free play is insufficient, it may result in brake drag.
Check the brake pad thickness through the caliper body inspection hole.
Pad thickness
Standard value : 11.0 mm ( 0.43 in)
Service limit : 2 mm (0.0787 in)
If the pad lining thickness is out of specilfication, left and right pads must be replaced as a complete set.
When the thickness difference between the left pad and right pad is large, check the sliding condition of the piston and the guide rod.
Check the rear disk brake pad thickness through the caliper body inspection hole.
Pad thickness
Standard value : 15.0 mm (0.59 in.)
Service limit : 2.0 mm (0.0787 in.)
If the pad thickness is out of specification, left and right pads must be replaced as a complete set.
When the thickness difference between the left pad and right pad is large, check the sliding condition of the piston and the guide rod.
