Toyota 4Runner: On-vehicle Inspection

Toyota 4Runner Service Manual / Brake / Brake System (other) / Hydraulic Brake Booster / On-vehicle Inspection

ON-VEHICLE INSPECTION

PROCEDURE

1. INSPECT BRAKE MASTER CYLINDER FLUID PRESSURE CHANGE

(a) Inspect the battery voltage.

Battery voltage:

11 to 14 V

(b) Turn the ignition switch off and depress the brake pedal more than 40 times.

HINT:

When pressure in the power supply system is released, the reaction force decreases and the stroke becomes longer.

SST: 09709-29018

Text in Illustration

*1	Brake Pedal Effort Gauge

(d) When the booster does not operate:

Depress the brake pedal and check the fluid pressure.

At 245 N (25 kgf, 55 lbf):

Front Brake Pressure	Rear Brake Pressure
2170 kPa (22.1 kgf/cm2, 315 psi) or higher	0 kPa (0 kgf/cm2, 0 psi)

At 343 N (35 kgf, 77 lbf):

Front Brake Pressure	Rear Brake Pressure
3130 kPa (31.9 kgf/cm2, 454 psi) or higher	0 kPa (0 kgf/cm2, 0 psi)

(e) When the booster operates:

Depress the brake pedal and check the fluid pressure.

(1) Turn the ignition switch to ON and wait until the pump motor has stopped.

(2) Depress the brake pedal and check the fluid pressure.

At 49 N (5 kgf, 11 lbf):

Front Brake Pressure	Rear Brake Pressure
1410 to 2610 kPa (14.4 to 26.6 kgf/cm2, 205 to 379 psi)	1620 to 2820 kPa (16.5 to 28.8 kgf/cm2, 235 to 409 psi)

Front Brake Pressure

Rear Brake Pressure

1410 to 2610 kPa

(14.4 to 26.6 kgf/cm2, 205 to 379 psi)

1620 to 2820 kPa

(16.5 to 28.8 kgf/cm2, 235 to 409 psi)

At 98 N (10 kgf, 22 lbf):

Front Brake Pressure	Rear Brake Pressure
3910 to 5110 kPa (39.9 to 52.1 kgf/cm2, 567 to 741 psi)	4220 to 5420 kPa (43.0 to 55.3 kgf/cm2, 612 to 786 psi)

Front Brake Pressure

Rear Brake Pressure

3910 to 5110 kPa

(39.9 to 52.1 kgf/cm2, 567 to 741 psi)

4220 to 5420 kPa

(43.0 to 55.3 kgf/cm2, 612 to 786 psi)

At 147 N (15 kgf, 33 lbf):

Front Brake Pressure	Rear Brake Pressure
6410 to 7610 kPa (65.4 to 77.6 kgf/cm2, 930 to 1104 psi)	6810 to 8010 kPa (69.4 to 81.1 kgf/cm2, 988 to 1162 psi)

Front Brake Pressure

Rear Brake Pressure

6410 to 7610 kPa

(65.4 to 77.6 kgf/cm2, 930 to 1104 psi)

6810 to 8010 kPa

(69.4 to 81.1 kgf/cm2, 988 to 1162 psi)

At 196 N (20 kgf, 44 lbf):

Front Brake Pressure	Rear Brake Pressure
8900 to 10100 kPa (90.8 to 103.0 kgf/cm2, 1291 to 1465 psi)	9410 to 10610 kPa (96.0 to 108.2 kgf/cm2, 1365 to 1539 psi)

Front Brake Pressure

Rear Brake Pressure

8900 to 10100 kPa

(90.8 to 103.0 kgf/cm2, 1291 to 1465 psi)

9410 to 10610 kPa

(96.0 to 108.2 kgf/cm2, 1365 to 1539 psi)

2. INSPECT BRAKE MASTER CYLINDER OPERATION

(a) Inspect the battery voltage.

Battery voltage:

11 to 14 V

(b) Turn the ignition switch off and depress the brake pedal more than 20 times.

HINT:

When pressure in the power supply system is released, the reaction force decreases and the stroke becomes longer.

If the pedal reaction force does not decrease, check the brake line and brake master cylinder and replace parts as necessary.

(d) Turn the ignition switch to ON and check the pump motor operation noise.

If the pump motor does not operate, check the wire harness and pump motor and replace parts as necessary (See page ).

(e) Connect the Techstream to the DLC3.

(f) Turn the ignition switch to ON.

(g) Select "Active Test" mode on the Techstream.

HINT:

Refer to the Techstream operator's manual for further details.

(h) Jack up and support the vehicle.

(i) Release the parking brake lever.

(j) Move the transfer shift lever to N and check that the rear wheels can be rotated by hand.

(k) Inspect front VSC solenoid (SMCF) operation.

(1) Select "VSC/TRAC Solenoid (SRCF)" on the Techstream.

(2) Turn the "VSC/TRAC Solenoid (SRCF)" on with the Techstream, depress the brake pedal with a stable force and check that the pedal cannot be depressed.

If the pedal can be depressed, replace the brake master cylinder.

NOTICE:

When operating the solenoid continuously, set the interval to more than 20 seconds.

HINT:

To protect the solenoids, the Techstream turns off automatically 2 sec. after every solenoid has been turned on.

(3) Release the brake pedal.

(4) When the solenoid is off, depress the brake pedal again and check that the brake pedal can be depressed.

If the pedal cannot be depressed, replace the brake master cylinder.

(l) Inspect front VSC solenoid (SREA) operation.

(1) Select "VSC/TRAC Solenoid (SRCF & SRCR)" on the Techstream.

(2) Turn the "VSC/TRAC Solenoid (SRCF & SRCR)" on simultaneously with the Techstream, and then depress the brake pedal with a stable force.

(3) When the solenoids are on, check that the front wheels cannot be rotated by hand.

If the front wheels can be rotated, replace the brake master cylinder.

NOTICE:

When operating the solenoid continuously, set the interval to more than 20 seconds.

HINT:

To protect the solenoids, the Techstream turns off automatically 2 sec. after every solenoid has been turned on.
When rotating the wheels quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheels as slowly as possible.

(4) When the solenoids are off, turn the "VSC/TRAC Solenoid (SRCF)" on again, and then depress the brake pedal. Check the front wheels by rotating them by hand.

If the front wheels cannot be rotated, replace the brake master cylinder.

(5) When the "VSC/TRAC Solenoid (SRCF)" is off, depress the brake pedal again and check that the brake pedal can be depressed.

If the pedal cannot be depressed, replace the brake master cylinder.

(m) Inspect front ABS solenoid (SFRH) operation.

(1) Select "ABS Solenoid (SFRH)" on the Techstream.

(2) Turn the "ABS Solenoid (SFRH)" on with the Techstream, and then depress the brake pedal with a stable force.

(3) When the solenoid is on, check the right front wheel by rotating it by hand.

If the right front wheel cannot be rotated, replace the brake master cylinder.

NOTICE:

When operating the solenoid continuously, set the interval to more than 20 seconds.

HINT:

To protect the solenoids, the Techstream turns off automatically 2 sec. after every solenoid has been turned on.
When rotating the wheel quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheel as slowly as possible.

(4) When the solenoid is off, depress the brake pedal again and check that the right front wheel cannot be rotated by hand.

If the right front wheel rotates, replace the brake master cylinder.

HINT:

When rotating the wheel quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheel as slowly as possible.

(n) Inspect front ABS solenoid (SFLH) operation.

(1) Select "ABS Solenoid (SFLH)" on the Techstream.

(2) Turn the "ABS Solenoid (SFLH)" on with the Techstream, and then depress the brake pedal with a stable force.

(3) When the solenoid is on, check the left front wheel by rotating it by hand.

If the left front wheel cannot be rotated, replace the brake master cylinder.

NOTICE:

When operating the solenoid continuously, set the interval to more than 20 seconds.

HINT:

To protect the solenoids, the Techstream turns off automatically 2 sec. after every solenoid has been turned on.
When rotating the wheel quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheel as slowly as possible.

(4) When the solenoid is off, depress the brake pedal again and check that the left front wheel cannot be rotated by hand.

If the left front wheel rotates, replace the brake master cylinder.

(o) Inspect front ABS solenoid (SFRR) operation.

(1) Select "ABS Solenoid (SFRR & SFRH)" on the Techstream.

(2) Depress the brake pedal with a stable force, and then turn the "ABS Solenoid (SFRR & SFRH)" on simultaneously with the Techstream.

(3) When the solenoids are on, check that the right front wheel by rotating it by hand.

If the right front wheel cannot be rotated, replace the brake master cylinder.

NOTICE:

When operating the solenoid continuously, set the interval to more than 20 seconds.

HINT:

To protect the solenoids, the Techstream turns off automatically 2 sec. after every solenoid has been turned on.
When rotating the wheel quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheel as slowly as possible.

(4) When the solenoids are off, depress the brake pedal again and check that the right front wheel cannot be rotated by hand.

If the right front wheel rotates, replace the brake master cylinder.

(p) Inspect front ABS solenoid (SFLR) operation.

(1) Select "ABS Solenoid (SFLR & SFLH)" on the Techstream.

(2) Depress the brake pedal with a stable force, and then turn the "ABS Solenoid (SFLR & SFLH)" on simultaneously with the Techstream.

(3) When the solenoids are on, check the left front wheel by rotating it by hand.

If the left front wheel cannot be rotated, replace the brake master cylinder.

NOTICE:

When operating the solenoid continuously, set the interval to more than 20 seconds.

HINT:

To protect the solenoids, the Techstream turns off automatically 2 sec. after every solenoid has been turned on.
When rotating the wheel quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheel as slowly as possible.

(4) When the solenoids are off, depress the brake pedal again and check that the left front wheel cannot be rotated by hand.

If the left front wheel rotates, replace the brake master cylinder.

(q) Inspect rear VSC solenoid (SREC) operation.

(1) Select "VSC/TRAC Solenoid (SRMF)" on the Techstream.

(2) Depress the brake pedal with a stable force, and then turn the "VSC/TRAC Solenoid (SRMF)" on with the Techstream.

(3) Release the brake pedal when the solenoid is on, and check that the rear wheels cannot be rotated by hand.

If the rear wheels can be rotated, replace the brake master cylinder.

NOTICE:

When operating the solenoid continuously, set the interval to more than 20 seconds.

HINT:

To protect the solenoids, the Techstream turns off automatically 2 sec. after every solenoid has been turned on.
When rotating the wheels quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheels as slowly as possible.

(4) When the solenoid is off, check the rear wheels by rotating them by hand.

If the rear wheels cannot be rotated, replace the brake master cylinder.

(r) Inspect rear VSC solenoid (STR) operation.

(1) Select "VSC/TRAC Solenoid (SRMR & SRMF)" on the Techstream.

(2) Turn the "VSC/TRAC Solenoid (SRMR & SRMF)" on simultaneously with the Techstream.

(3) When the solenoids are on, check that the rear wheels cannot be rotated by hand.

If the rear wheels can be rotated, replace the brake master cylinder.

NOTICE:

When operating the solenoid continuously, set the interval to more than 20 seconds.

HINT:

To protect the solenoids, the Techstream turns off automatically 2 sec. after every solenoid has been turned on.
When rotating the wheels quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheels as slowly as possible.

(4) When the solenoids are off, turn the "VSC/TRAC Solenoid (SRMF)" on again, and check the rear wheels by rotating them by hand.

If the rear wheels cannot be rotated, replace the brake master cylinder.

(5) When the "VSC/TRAC Solenoid (SRMF)" is off, depress the brake pedal again and check that the rear wheels cannot be rotated by hand.

If the rear wheels can be rotated, replace the brake master cylinder.

(s) Inspect rear ABS solenoid (SRRH) operation.

(1) Select "ABS Solenoid (SRRH)" on the Techstream.

(2) Turn the "ABS Solenoid (SRRH)" on with the Techstream, and then depress the brake pedal with a stable force.

(3) When the solenoid is on, check the right rear wheel by rotating it by hand.

If the right rear wheel cannot be rotated, replace the brake master cylinder.

NOTICE:

When operating the solenoid continuously, set the interval to more than 20 seconds.

HINT:

To protect the solenoids, the Techstream turns off automatically 2 sec. after every solenoid has been turned on.
When rotating the wheel quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheel as slowly as possible.

(4) When the solenoid is off, depress the brake pedal again and check that the right rear wheel cannot be rotated by hand.

If the right rear wheel rotates, replace the brake master cylinder.

HINT:

When rotating the wheel quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheel as slowly as possible.

(t) Inspect rear ABS solenoid (SRLH) operation.

(1) Select "ABS Solenoid (SRLH)" on the Techstream.

(2) Turn the "ABS Solenoid (SRLH)" on with the Techstream, and then depress the brake pedal with a stable force.

(3) When the solenoid is on, check the left rear wheel by rotating it by hand.

If the left rear wheel cannot be rotated, replace the brake master cylinder.

NOTICE:

When operating the solenoid continuously, set the interval to more than 20 seconds.

HINT:

To protect the solenoids, the Techstream turns off automatically 2 sec. after every solenoid has been turned on.
When rotating the wheel quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheel as slowly as possible.

(4) When the solenoid is off, depress the brake pedal again and check that the left rear wheel cannot be rotated by hand.

If the left rear wheel rotates, replace the brake master cylinder.

(u) Inspect rear ABS solenoid (SRRR) operation.

(1) Select "ABS Solenoid (SRRR & SRRH)" on the Techstream.

(2) Depress the brake pedal with a stable force, and then turn the "ABS Solenoid (SRRR & SRRH)" on simultaneously with the Techstream.

(3) When the solenoids are on, check the right rear wheel by rotating it by hand.

If the right rear wheel cannot be rotated, replace the brake master cylinder.

NOTICE:

When operating the solenoid continuously, set the interval to more than 20 seconds.

HINT:

To protect the solenoids, the Techstream turns off automatically 2 sec. after every solenoid has been turned on.
When rotating the wheel too quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheel as slowly as possible.

(4) When the solenoids are off, depress the brake pedal again and check that the right rear wheel cannot be rotated by hand.

If the right rear wheel rotates, replace the brake master cylinder.

(v) Inspect rear ABS solenoid (SRLR) operation.

(1) Select "ABS Solenoid (SRLR & SRLH)" on the Techstream.

(2) Depress the brake pedal with a stable force, and then turn the "ABS Solenoid (SRLR & SRLH)" on simultaneously with the Techstream.

(3) When the solenoids are on, check the left rear wheel by rotating it by hand.

If the left rear wheel cannot be rotated, replace the brake master cylinder.

NOTICE:

When operating the solenoid continuously, set the interval to more than 20 seconds.

HINT:

To protect the solenoids, the Techstream turns off automatically 2 sec. after every solenoid has been turned on.
When rotating the wheel too quickly, the fail-safe function is activated and judgment cannot be made properly. Rotate the wheel as slowly as possible.

(4) When the solenoids are off, depress the brake pedal again and check that the left rear wheel cannot be rotated by hand.

If the left rear wheel rotates, replace the brake master cylinder.

(w) Lower the vehicle.

(x) Disconnect the Techstream.

3. INSPECT BRAKE FLUID LEVEL

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