NISSAN X-TRAIL 2003 Electronic Repair Manual

BRAKE BOOSTER
BR-17
C
D
E
G
H
I
J
K
L
MA
B
BR
BRAKE BOOSTERPFP:47200
On-Vehicle Inspection and ServiceEFS000CC
FUNCTION INSPECTION
With the engine stopped, discharge stored vacuum by depressing
brake pedal several times at 5 second intervals. With the brake
pedal fully depressed, start the engine.between Confirm that clear-
ance between brake pedal and the floor panel decreases when
engine vacuum stabilizes.
AIRTIGHTNESS INSPECTION
lRun the engine at idle for approximately 1 minute. Stop it after
applying vacuum to the booster. Depress the brake pedal sev-
eral times with normal force to discharge the stored vacuum.
Confirm that clearance between brake pedal and the floor panel
gradually increases as the brake pedal is depressed.
lRun the engine. Depress and hold the brake pedal then stop the
engine. Keep the brake pedal depressed for 30 seconds or more
and make sure the pedal stroke does not change.
Removal and InstallationEFS000CD
REMOVAL
CAUTION:
lBe careful not to deform or bend brake piping while removing and installing the brake booster.
lReplace clevis pin if it is damaged.
lBe careful not to damage brake booster stud bolt threads. If brake booster is tilted or inclined dur-
ing installation, the dash panel may damage the threads.
lBe sure to install the check valve in the correct orientation.
1. Remove vacuum piping from the brake booster.
2. Remove master cylinder.
3. Remove snap pin and clevis pin on passenger compartment clevis. Remove input rod from the brake
pedal.
4. Remove brake booster and brake pedal assembly mounting nuts.
5. Remove booster assembly from the engine compartment.
INSPECTION AFTER REMOVAL
Output rod length inspection
1. Using a handy vacuum pump, apply a vacuum of -66.7 kPa (-500 mmHg,-19.69 inHg) to the brake
booster.
BRA0037D
SBR365AA
SFIA0139E

BR-18
BRAKE BOOSTER
2. Place an output rod gauge in the master cylinder. Rotate the
screw until the gauge contacts the primary piston.
3. Turn output rod gauge upside down to secure A. Adjust it with B
until clearance between output rod and screw is 0 mm.
INSTALLATION
1. Loosen lock nut to adjust input rod length so that length B (in the
figure) satisfies the specified value.
2. After adjusting B, temporarily tighten lock nut to install booster
assembly to vehicle.
3. Connect brake pedal to input rod clevis.
4. Connect brake pedal assembly mounting nuts and tighten to the
specified torque.
5. Connect master cylinder to the booster assembly.
6. Adjust brake pedal height and play.
7. Tighten input rod lock nut to the specified torque.
8. Bleed air. Refer toBR-10, "
Bleeding Brake System". Reference value at vacuum of -66.7 kPa (-500 mmHg, -
19.69 inHg):
10.4 mm (0.409 in)
SBR208E
Length B standard : 125 mm (4.92 in)
SGIA0060E

VACUUM LINES
BR-19
C
D
E
G
H
I
J
K
L
MA
B
BR
VACUUM LINESPFP:41920
Removal and InstallationEF S0 00 CE
CAUTION:
lBecause vacuum hose contains a check valve, it must be installed in the correct orientation. Refer
to the stamp or label to confirm correct installation. The brake booster will not operate normally if
the hose is installed in the wrong direction.
lInsert the vacuum hose for at least 24 mm (0.94 in).
lNever use lubricating oil during assembly.
InspectionEFS000CF
VISUAL INSPECTION
Check for improper assembly, damage and aging.
SFIA0369E
1 Vacuum hose 2 Vacuum tube 3 Clip
4Clamp
SBR225B

BR-20
VACUUM LINES
CHECK VALVE INSPECTION
Quick Inspection
The check valve is incorporated in the vacuum hose. Blow air into
vacuum hose to inspect the check valve. The check valve is normal
when air can only be blown in from the booster side.
CAUTION:
If air can blow both ways through the vacuum hose, replace
hose and check valve as a set.
Airtightness Inspection
Use a hand-held vacuum pump to check.
SFIA0209E
When connected to booster side (1):
Vacuum decrease should be within 1.3 kPa
(10 mmHg, 0.39 inHg) for 15 seconds under
a vacuum of -66.7 kPa (-500 mmHg, -19.69
inHg)
When connected to engine side (2):
No vacuum will be applied
SFIA0210E

FRONT DISC BRAKE
BR-21
C
D
E
G
H
I
J
K
L
MA
B
BR
FRONT DISC BRAKEPFP:41000
ComponentEFS000CG
WA RN ING:
lClean brake pads with a vacuum dust collector to minimize the hazard of airborne particles or
other materials.
CAUTION:
lWhen cylinder body is open, do not depress brake pedal because piston will pop out.
lBe careful not to damage piston boot or get oil on rotor. Always replace shims when replacing
pads.
lIf shims are rusted or show peeling of the rubber coat, replace them with new shims.
lIt is not necessary to remove connecting bolt except for disassembly or replacement of caliper
assembly. In this case, suspend cylinder body with wire so as not to stretch brake hose.
lBurnish the brake contact surfaces after refinishing or replacing drums or rotors, after replacing
pads or linings, or if a soft pedal occurs at very low mileage. Refer toBR-10, "
Brake Burnishing
Procedure".
InspectionEFS000CH
PAD THICKNESS
Check pad thickness by lifting vehicle, removing the wheel, and
looking through check hole on cylinder body. If necessary, use a
scale.
SFIA0328E
1 Torque member 2 Slid pin boot 3 Slid pin
4 Outer shim cover 5 Outer shim 6 Outer pad
7 Pad retainer 8 Inner pad 9 Inner shim
10 Inner shim cover 11 Piston boots 12 Piston
13 2 piston seal 14 Cylinder body 15 Copper washer
16 Air bleeder 17 Brake hose union bolt
Standard pad thickness : 11 mm (0.43 in)
Pad wear limit : 2.0 mm (0.079 in)
MAA0439D

BR-22
FRONT DISC BRAKE
Pad Replacement
EFS000CI
REMOVAL
CAUTION:
When replacing brake pads, always replace inner shims, outer shims, and shim covers as a set.
1. Remove master cylinder reservoir tank cap.
2. Remove lower sliding pin bolt.
3. Hang cylinder body with a wire, and remove pads, pad retainers,
shims and pad return springs.
INSTALLATION
1. Apply brake grease on back of the pad and both sides of the shim. Install inner shim and inner shim cover
to inner pad, outer shim to outer pad.
2. Apply brake grease on the pad retainer pad contact surface. Install pad retainers, pads and pad return
springs to the torque member.
3. Connect cylinder body to the torque member.
CAUTION:
When replacing pads with new ones, press piston in until the pads can be installed. Carefully mon-
itor brake master cylinder reservoir fluid level. Brake fluid will return, raising master cylinder res-
ervoir tank fluid level.
4. Insert lower sliding pin bolt and tighten to the specified torque.
5. Check brakes for drag.
Caliper Removal and InstallationEFS000CJ
REMOVAL
1. Connect a vinyl tube to the air bleeder.
2. Drain brake fluid gradually from air bleeder while depressing brake pedal.
SBR433D
SBR932C

FRONT DISC BRAKE
BR-23
C
D
E
G
H
I
J
K
L
MA
B
BR
3. Remove union bolts and torque member mounting bolts, and
remove caliper assembly.
4. Remove disc rotor.
INSTALLATION
CAUTION:
lRefill with new brake fluid “DOT 3” or “DOT 4”.
lNever reuse drained brake fluid.
1. Install disc rotor.
2. Install caliper assembly. Tighten mounting bolts to the specified torque.
CAUTION:
Before installing caliper assembly, wipe oil and grease on the trailing arm washer seats and cali-
per assembly mounting surface.
3. Connect brake hose to caliper assembly and tighten union bolts to the specified torque.
CAUTION:
lDo not reuse the copper washer for union bolts.
lSecurely assemble brake hose to protrusions on cylinder body.
4. Bleed air. Refer toBR-10, "
Bleeding Brake System".
Caliper Disassembly and AssemblyEF S0 00 CK
DISASSEMBLY
WA RN ING:
Be careful not to pinch your fingers in the piston.
CAUTION:
Be careful not to damage the cylinder inner wall.
1. Place a wooden block as shown in the figure. Blow air into union
bolt mounting hole to remove pistons and piston boots.
SBR979B
BRB0032D

BR-24
FRONT DISC BRAKE
2. Using a slotted screwdriver, remove piston seals.
INSPECTION AFTER DISASSEMBLY
Cylinder Body
CAUTION:
Use new brake fluid to clean. Never use mineral oils such as gasoline or kerosene.
lCheck cylinder inner wall for corrosion, wear and damage. If corrosion, wear or damage is detected,
replace the cylinder body.
lMinor flaws caused by corrosion or foreign material can be removed by polishing the surface with fine
sandpaper. Replace the cylinder body, if necessary.
Torque Member
Check for wear, cracks and damage. If wear, cracks or damage is detected, replace the applicable part.
Piston
CAUTION:
The piston sliding surface is plated. Do not polish with sandpaper.
Check piston surface for corrosion, wear and damage. If corrosion, wear or damage is detected, replace the
applicable part.
Sliding Pin, Pin Bolt, and Pin Boot
Check sliding pin and sliding pin boot for wear, damage and cracks. If corrosion, wear or damage is detected,
replace the applicable part.
DISC ROTOR INSPECTION
Visual Inspection
Check surface of the disc rotor for uneven wear, cracks and serious damage. If uneven wear, cracks or seri-
ous damage is detected, replace it.
Run Out Inspection
1. Using wheel nuts, fix the disc rotor to the wheels hub. (2 or more positions)
2. Using a dial indicator, check run out.
CAUTION:
Before measuring, make sure that the axle endplay is 0 mm
(0 in).
3. If the run out is outside the limit, find the minimum run out point
by shifting the mounting positions of the disc rotor and wheel hub by one hole.
SFIA0141E
Measurement point:
At a point 10 mm (0.39 in) from the outer edge of the
disc.
Run out limit: 0.04 mm (0.0016 in) or
less
BRA0013D

FRONT DISC BRAKE
BR-25
C
D
E
G
H
I
J
K
L
MA
B
BR
Thickness Inspection
Using a micrometer, check thickness of the disc rotor. If the thick-
ness is outside the standard, replace the disc rotor.
ASSEMBLY
CAUTION:
When assembling, do not use rubber grease.
1. Apply rubber lubricant to piston seals, and install them to cylin-
der body.
CAUTION:
Do not reuse piston seals.
2. Apply brake fluid or rubber lubricant to piston boots. Cover pis-
ton end with piston boot. Install cylinder side lip on piston boot
properly into groove on cylinder body.
CAUTION:
Do not reuse piston boot.
3. Apply brake fluid to piston. Press piston into cylinder body by
hand. Assemble piston side lip on piston boot properly into
groove on piston.
CAUTION:
Press piston evenly and change pressing point to prevent
cylinder inner wall from being rubbed.
BRAKE BURNISHING PROCEDURE
Burnish the brake contact surfaces according to the following procedure after refinishing or replacing drums or
rotors, after replacing pads or linings, or if a soft pedal occurs at very low mileage.
CAUTION:
Only perform this procedure under safe road and traffic conditions. Use extreme caution.
1. Drive the vehicle on a straight smooth road at 50 km/h (31MPH).Standard thickness : 28.0 mm (1.102 in)
Wear limit : 26.0 mm (1.024 in)
Maximum uneven wear (measured at 8 positions):
0.02 mm (0.0008 in) or less
SBR020B
SFIA0154E
SFIA0155E
SBR574

BR-26
FRONT DISC BRAKE
2. Use medium brake pedal/foot effort to bring the vehicle to a complete stop from 50 km/h (31 MPH).
Adjust brake pedal/foot pressure such that vehicle stopping time equals 3 to 5 seconds.
3. To cool the brake system, drive the vehicle at 50 km/h (31 MPH) for 1 minute without stopping.
4. Repeat steps 1 to 3, 10 times or more to complete the burnishing procedure.