Basic Brake System: Diagnosis Mitsubishi Outlander III

SYMPTOM CHART

PROBLEM SYMPTOMS

DIAGNOSIS

1. STEP 1. Check for oil, water, etc., on the pad contact surface of all brakes. Q: Is oil, water, etc., on the pad contact surface? YES: Replace the part and determine the source/cause of foreign material. Then go to Step 5 . NO: Go to Step 2.
2. STEP 2. Check disc brake pistons for smooth operation. With engine not running, depress the brake pedal rapidly several times to deplete booster vacuum reserves. Test each disc brake assembly one at a time. Remove the lower caliper bolt, then remove caliper from mount. Have an assistant slowly depress the brake pedal. Confirm piston(s) extend slowly and smoothly with no jumpiness. Repeat for each disc brake assembly. Q: Do (does) the piston(s) move correctly? YES: Go to Step 3. NO: Disassemble and inspect the brake assembly (Front: refer to «DISASSEMBLY AND ASSEMBLY»(ref-593035-S09377232612014011300000) , Rear: refer to «DISASSEMBLY AND ASSEMBLY»(ref-593035-S01086148252014011300000) . Then go to Step 5 .
3. STEP 3. Check brake disc(s) for runout. Refer to «BRAKE DISC CHECK»(ref-593035-S15730234822014011300000) . Q: Is runout outside of specifications? YES: Repair or replace the brake disc(s) as necessary. Then go to Step 5 . NO: Go to Step 4.
4. STEP 4. Check brake discs for correct thickness. Refer to «BRAKE DISC CHECK»(ref-593035-S15730234822014011300000) . Q: Is the thickness outside of specifications? YES: Repair or replace the brake disc(s) as necessary. Then go to Step 5. NO: Perform the brake line bleeding. Then go to Step 5.
5. STEP 5. Retest the system. Q: Is the symptom eliminated? YES: The procedure is complete. NO: Start over at Step 1 . If a new symptom appears, refer to the appropriate «SYMPTOM CHART»(ref-593035-S32441809142014011300000) .

1. STEP 1. Check that the specified brake fluid is used, its level is correct, and no contamination is found. Q: Is there a fault? YES: Refill or replace with the specified brake fluid DOT 3 or DOT 4. Bleed the brakes if necessary (Refer to «BLEEDING»(ref-593035-S10293760512014011300000) ). Then go to Step 6 . NO: Go to Step 2.
2. STEP 2. Check for spongy (not firm) brakes. With engine not running, depress the brake pedal rapidly several times to deplete the booster vacuum reserve. With the brake pedal fully released, depress the brake pedal slowly until it stops. With a measuring device (ruler, etc.) next to the brake pedal, depress the pedal firmly and measure the distance the pedal traveled. Q: Is the distance greater than 20 mm (0.8 inch)? YES: Bleed the brakes to remove air in the fluid (Refer to «BLEEDING»(ref-593035-S10293760512014011300000) ). Then go to Step 6 . NO: Go to Step 3.
3. STEP 3. Check the brake booster function. Refer to «BRAKE BOOSTER OPERATION CHECK»(ref-593035-S38825291152014011300000) . Q: Is there a fault? YES: Replace the brake booster. Then go to Step 6 . NO: Go to Step 4.
4. STEP 4. Check for pinched or restricted brake tube or hose. Q: Is there a pinched or restricted brake tube or hose? YES: Replace that complete section of brake tube or brake hose. Then go to Step 6 . NO: Go to Step 5.
5. STEP 5. Check for oil, water, etc., on the pad contact surfaces of all brakes. Q: Is oil, water, etc., on the pad contact surface? YES: Replace the part and determine the source/cause of foreign material. Recheck symptom. Then go to Step 6. NO: The procedure is complete. If condition persists for vehicles without ABS, go to Step 6.
6. STEP 6. Recheck symptom. Q: Is the symptom eliminated? YES: The procedure is complete. NO: Start over at step 1 . If a new symptom surfaces, refer to the appropriate «SYMPTOM CHART»(ref-593035-S32441809142014011300000) .

1. STEP 1. Check for spongy (not firm) brakes. With engine not running, depress the brake pedal rapidly several times to deplete booster vacuum reserve. With the brake pedal fully released, depress the brake pedal slowly until it stops. With a measuring device (ruler, etc.) next to the brake pedal, depress the pedal firmly and measure the distance the pedal traveled. Q: Is the distance greater than 20 mm (0.8 inch)? YES: Bleed the brakes to remove air in the fluid (Refer to «BLEEDING»(ref-593035-S10293760512014011300000) ). Then go to Step 6 . NO: Go to Step 2.
2. STEP 2. Check the pad for wear. Refer to «BRAKE PAD CHECK»(ref-593035-S38656040352014011300000) . Q: Is the pad thickness outside of specifications? YES: Replace the part. Then go to Step 6 . NO: Go to Step 3.
3. STEP 3. Check the vacuum hose and check valve for damage. Refer to «CHECK VALVE OPERATION CHECK»(ref-593035-S33858432392014011300000) . Q: Is there a damage? YES: Replace the part. Then go to Step 6 . NO: Go to Step 4.
4. STEP 4. Check for brake fluid leaks. Q: Is there a leak? YES: Check the connection for looseness, corrosion, etc. Clean and repair as necessary. If leaking in any tube or hose section, replace the complete tube or hose. Then go to Step 6 . NO: Go to Step 5.
5. STEP 5. Check the master cylinder assembly. Remove the master cylinder assembly (Refer to «MASTER CYLINDER ASSEMBLY AND BRAKE BOOSTER ASSEMBLY»(ref-593035-S42418374952014011300000) ). Check for brake fluid leaks from the master cylinder assembly seal. Q: Is a brake fluid leaking from the master cylinder assembly seal present? YES: Replace the master cylinder assembly and the brake booster assembly (Refer to «MASTER CYLINDER ASSEMBLY AND BRAKE BOOSTER ASSEMBLY»(ref-593035-S42418374952014011300000) ). Then go to Step 6. NO: Go to Step 6.
6. STEP 6. Recheck symptom. Q: Is the symptom eliminated? YES: The procedure is complete. NO: Start over at step 1 . If a new symptom surfaces, refer to the «SYMPTOM CHART»(ref-593035-S32441809142014011300000) .

Scheme 1

Scheme 2

1. STEP 1. Check the parking brake operating lever return. Q: Is the operation faulty? YES: Repair it. Then go to Step 6 . NO: Go to Step 2.
2. STEP 2. Check the brake shoe springs for breakage. Q: Are the brake shoe springs broken? YES: Replace the spring. Then go to Step 6 . NO: Go to Step 4 .
3. STEP 3. Check the parking brake pull amount. Refer to «PARKING BRAKE LEVER STROKE CHECK AND ADJUSTMENT»(ref-593016-S18813318992014011300000) . Q: Is there a fault? YES: Adjust it. Then go to Step 6 . NO: Go to Step 4.
4. STEP 4. Check port for clogging. Q: Is the port clogged? YES: Repair it. Then go to Step 6 . NO: Go to Step 5.
5. STEP 5. Check disk brake pistons for sticking. Depress the brake pedal, then release. Confirm each wheel spins freely. Q: Does any wheel stick? YES: Inspect that brake assembly. Then go to Step 6. NO: Go to Step 6.
6. STEP 6. Recheck symptom. Q: Is the symptom eliminated? YES: The procedure is complete. NO: Start over at step 1 . If a new symptom surfaces, refer to the «SYMPTOM CHART»(ref-593035-S32441809142014011300000) .

Scheme 3

Scheme 4

1. STEP 1. Check the front brakes, then rear brakes, for metal-to-metal condition. Q: Is any metal-to-metal contact evident? YES: Repair or replace the components. Then go to Step 6 . NO: Go to Step 2.
2. STEP 2. Check for interference between the caliper and wheel. Q: Is there any interference? YES: Repair or replace the part. Then go to Step 6 . NO: Go to Step 3.
3. STEP 3. Check for interference between the dust cover and brake disc. Q: Is there any interference? YES: Repair or replace the part. Then go to Step 6 . NO: Go to Step 4.
4. STEP 4. Check the brake drums or discs for cracks. Q: Are there cracks? YES: Repair or replace the part. Then go to Step 6 . NO: Go to Step 5.
5. STEP 5. Check for bent backing plate(s). Q: Is (Are) the backing plate(s) bent? YES: Repair or replace the part. Then go to Step 6. NO: Go to Step 6.
6. STEP 6. Recheck symptom. Q: Is the symptom eliminated? YES: The procedure is complete. NO: Start over at step 1 . If a new symptom surfaces, refer to the «SYMPTOM CHART»(ref-593035-S32441809142014011300000) .

1. STEP 1. Check the brake disc and pads for wear or cutting. Q: Is there wear or cutting? YES: Repair or replace the part. Then go to Step 4 . NO: Go to Step 2.
2. STEP 2. Check the calipers for rust. Q: Is there any rust? YES: Remove the rust. Then go to Step 4 . NO: Go to Step 3.
3. STEP 3. Adjust the brake pedal. Refer to «BRAKE PEDAL PLAY CHECK AND ADJUSTMENT»(ref-593035-S09898869132014011300000) . Q: Is the brake pedal adjusted correctly? YES: Go to Step 4. NO: Adjust the brake pedal. Then go to Step 4.
4. STEP 4. Recheck symptom. Q: Is the symptom eliminated? YES: The procedure is complete. NO: Start over at step 1 . If a new symptom surfaces, refer to the «SYMPTOM CHART»(ref-593035-S32441809142014011300000) .

1. STEP 1. Check whether the backing plate is bent or loose and interfering with the drum. Q: Is there a fault? YES: Replace the part. Then go to Step 9 . NO: Go to Step 2.
2. STEP 2. Check whether the drum is damaged due to interference with the backing plate or shoe. Q: Is there any damage? YES: Replace the part. Then go to Step 9 . NO: Go to Step 3.
3. STEP 3. Check the brake drum for wear and the shoe spring for damage. Q: Is there any wear or damage? YES: Replace the part. Then go to Step 9 . NO: Go to Step 4.
4. STEP 4. Check the brake discs for rust. Q: Are the brake discs rusted? YES: Remove the rust by using sand paper. If still rusted, turn the rotors with an on-the-car brake lathe. Then go to Step 9 . NO: Go to Step 5.
5. STEP 5. Check the brake pads for correct installation. Q: Are the pads installed incorrectly? YES: Repair the pads. Then go to Step 9 . NO: Go to Step 6.
6. STEP 6. Check the calipers for correct installation. Q: Are the calipers installed incorrectly? YES: Repair the calipers. Then go to Step 9 . NO: Go to Step 7.
7. STEP 7. Check the wheel bearings for end play. Refer to «WHEEL BEARING END PLAY CHECK»(ref-593009-S28584894502014011300000) < Front >, «WHEEL BEARING END PLAY CHECK»(ref-592983-S23655325442014011300000) < Rear (FWD) > or «WHEEL BEARING END PLAY CHECK»(ref-593030-S34282252312014011300000) < Rear (AWD) >. Q: Does the measured end play exceed the limit? YES: Replace the faulty hub assembly. Then go to Step 9 . NO: Go to Step 8.
8. STEP 8. Adjust the brake pedal. Refer to «BRAKE PEDAL PLAY CHECK AND ADJUSTMENT»(ref-593035-S09898869132014011300000) . Q: Is the brake pedal adjusted correctly? YES: Go to Step 9. NO: Adjust the brake pedal. Then go to Step 9.
9. STEP 9. Recheck symptom. Q: Is the symptom eliminated? YES: The procedure is complete. NO: Start over at step 1 . If a new symptom surfaces, refer to the «SYMPTOM CHART»(ref-593035-S32441809142014011300000) .

Scheme 5

Scheme 6

1. STEP 1. Check whether foreign material has entered the wheel covers. Q: Is there any foreign material? YES: Remove it. Then go to Step 5 . NO: Go to Step 2.
2. STEP 2. Check for looseness of the wheel nuts. Q: Are the wheel nuts loose? YES: Tighten to 98 ± 10 N.m (73 ± 7 ft-lb). Then go to Step 5 . NO: Go to Step 3.
3. STEP 3. Check for looseness of the caliper installation bolt. Q: Is the caliper installation bolt loose? YES: Tighten to 100 ± 10 N.m (74 ± 7 ft-lb) for the front caliper. Tighten to 55 ± 5 N.m (41 ± 3 ft-lb) for the rear caliper. Then go to Step 5 . NO: Go to Step 4.
4. STEP 4. Check the wheel bearings for end play. Refer to «WHEEL BEARING END PLAY CHECK»(ref-593009-S28584894502014011300000) < Front >, «WHEEL BEARING END PLAY CHECK»(ref-592983-S23655325442014011300000) < Rear (FWD) > or «WHEEL BEARING END PLAY CHECK»(ref-593030-S34282252312014011300000) < Rear (AWD) >. Q: Does the measured end play exceed the limit? YES: Replace the faulty hub assembly. Then go to Step 5. NO: Go to Step 5.
5. STEP 5. Recheck symptom. Q: Is the symptom eliminated? YES: The procedure is complete. NO: Start over at step 1 . If a new symptom surfaces, refer to the «SYMPTOM CHART»(ref-593035-S32441809142014011300000) .

BRAKE PEDAL INSPECTION

Scheme 7

Scheme 8

Scheme 9

1. Turn up the floor carpet under the brake pedal.
2. Remove the stoplight switch (Refer to «REMOVAL AND INSTALLATION»(ref-593035-S26122287572014011300000) ).
3. Use a needle or similar tool to measure the dimension A in the illustration (distance from the dash panel pad surface to the dash panel).
4. Measure the dimension B in the illustration (distance from the pedal pad surface to the dash panel pad surface).
5. Make sure that the total of the dimensions A and B measured in Steps 2 and 3 (brake pedal height) is within the standard value. Standard value (A + B): 221.8 - 227.8 mm (8.7 - 9.0 inch)
6. When the brake pedal height is not within the standard value, inspect the brake pedal in the following procedure. Remove the brake pedal assembly (Refer to «REMOVAL AND INSTALLATION»(ref-593035-S26122287572014011300000) ). Check the removed brake pedal assembly for distortion, and replace it when deformed (Refer to «BRAKE PEDAL DISTORTION CHECK»(ref-593035-S29850054662014011300000) ). Install the brake pedal assembly (Refer to «REMOVAL AND INSTALLATION»(ref-593035-S26122287572014011300000) ). NOTE: When installing, compress the dash panel pad. Measure the brake pedal height again, and make sure that it is within the standard value (A + B). When the measured value is not within the standard value, measure the dimension C in the illustration (distance from the stud bolt end to the clevis hole center), and make sure it is within the standard value (C). Standard value (C): 75.8 - 80.2 mm (2.98 - 3.16 inch) When the measured value is not within the standard value (C), replace the brake booster (Refer to «REMOVAL AND INSTALLATION»(ref-593035-S18214551992014011300000) ).
7. After checking the brake pedal height, install the stoplight switch in the following procedure: Screw in the stoplight switch until its thread contacts the pedal stopper, then turn the switch approximately one eighth of a clockwise turn to fix it. While doing this, pull and hold the brake pedal by hand. Check that the clearance between the stoplight switch and the pedal stopper is as shown in the illustration. CAUTION: Make sure that the stoplight is not illuminated when the brake pedal is not depressed. Connect the stoplight switch connector.
8. Check the key interlock mechanism and the shift lock mechanism (Refer to «SHIFT LOCK MECHANISM CHECK»(ref-593043-S00677625252014011300000) ).
9. Recover the floor carpet under the brake pedal.

Scheme 10

1. With the engine stopped, depress the brake pedal 2 or 3 times to relieve the vacuum in the brake booster. Then, press the brake pedal with your finger and check if the pedal stroke until the pedal becomes heavy (play) is within the standard value. Standard value (B): 3 - 8 mm (0.12 - 0.31 inch)
2. When the brake pedal play is not within the standard value, check the brake pedal-to-clevis pin looseness, clevis pin-to-booster operating rod looseness, brake pedal height, and stoplight switch position, and adjust or replace as necessary.

Scheme 11

1. Turn up the floor carpet under the brake pedal.
2. Start the engine and depress the brake pedal with approximately 500 N (112 pounds), and measure clearance between the brake pedal and the floor panel. Standard value (C): 85 mm (3.3 inch) or more
3. When the clearance is not within the standard value, check for the air in the brake line and thickness of the disc brake pad, and correct or replace as necessary.
4. Recover the floor carpet under the brake pedal.

Scheme 12

Scheme 13

Scheme 14

1. Carry out the simplified brake booster operation check in the following procedure: Run the engine for 1 to 2 minutes, and then stop. Depress the brake pedal with normal depression force. The result is judged as "Good" when the pedal stroke is great at the first depression, and becomes smaller as you repeat depressing the pedal. If the pedal stroke does not change, the result is judged as "No Good." With the engine stopped, depress the brake pedal several times. Keep the brake pedal depressed and start the engine. At this time, when the pedal moves down slightly, the result is judged as "Good." The result is judged as "No Good" if the pedal does not moves down. With the engine running, depress the brake pedal. Stop the engine in this condition. The result is judged as "Good" when the pedal height does not change for approximately 30 seconds. The result is judged as "No Good" if the pedal moves up.
2. The brake booster is judged as normal when the results of all the above checks are "Good." When one or more of the above check results are "No Good," then the check valve, vacuum hose, or brake booster is suspected faulty.

Scheme 15

1. Remove the check valve (Refer to «REMOVAL AND INSTALLATION»(ref-593035-S18214551992014011300000) ). CAUTION: Replace the check valve when it is faulty.
2. Using a vacuum pump, check operation of the check valve. VACUUM PUMP CONNECTION CONDITION Vacuum pump connection Normal condition When connected to the booster side (1) Vacuum is generated and maintained. When connected to the engine side (2) No vacuum is generated.

INSPECTION

1. Check the cylinder for wear, damage or rust.
2. Check the piston surface for wear, damage or rust.
3. Check the caliper body for wear.
4. Check the pad for damage or adhesion of grease, check the backing metal for damage.

BRAKE PAD WEAR INSPECTION

Measure the brake pad thickness at the most worn area. If the brake pad thickness is less than the limit value, replace the brake pad.

Standard value: 9.0 mm (0.35 inch)

Limit: 1.5 mm (0.06 inch)

Scheme 16