brakes MITSUBISHI 3000GT 1991 User Guide

L,
SERVICE
BRAKES
CONTENTSM35AA..
ANTI-LOCK BRAKING SYSTEM TROUBLESHOOTING7Actuator Test Function
. . . . ..___..._____.__................................ I 2, 36Check Using Self Diagnosis Function __._.....,_._.._____........ 11, 28
Diagnosis Code Chart ..,,........,......_..................................,. 1 I, 28
How to Use the Troubleshooting Flow Chart
_____.___......._._.7Method of Clearing Diagnosis Code Memory._.,._...... 12, 30
Particular Phenomena of the Anti-lock Braking System
7Troubleshooting (ABS-AWD) ._______._.._...........................,... 26
Troubleshooting (ABS-FWD) ______.._._........_...........,.....,.....,....8
TroubleshootingMethods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
BRAKE LINE . . . . . . .._.......................................................................71
BRAKEPEDAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
ELECTRONIC CONTROL UNIT (ABS). . . . .._._..___..__._............93/
L
FRONT DISC BRAKE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73G SENSOR (AWD-ABS)’
____.____.___.__._._.................,,......,.....,.... 92
HYDRAULIC UNIT (ABS) .___.._._._._.______.............,...,,..........~ .,_____86
MASTER CYLINDER AND BRAKE BOOSTER ..__.._____.._____67SPECIFICATIONS ._....._.___.....................................
REAR DISC BRAKE . . . . . . .._..._._.___................................................81
SERVICE ADJUSTMENT PROCEDURES..___........45Bleeding48
Brake Booster Operating Inspection.
46
Brake Drum Inside Diameter Check. . .56
BrakeFluidLevelSensor Check.46
Brake Lining and Brake Drum Connection Check56Brake
Linrng Thickness Check............................................Brake Pedal Inspection and Adjustment............................Check Valve Operation Check............................................Front Brake Disc Run-out Check........................................Front Brake Disc Run-out Correction................................Front Disc Brake Pad Check and Replacement................Inspection of Front Brake Disc Thickness........................Inspection of Hydraulic Unit................................................Inspectton of Power Relay....................................................Inspection of Valve Relay and Motor Relay (ABS)............Measurement of Wheel Speed Sensor Output Voltage
Proportioning Valve Function Test
....................................Rear Brake Disc Run-out Check........................................Rear Brake Disc Run-out Correction................................Rear Brake Disc Thickness Check....................................Rear Disc Brake Pad Check and Replacement................Remedy in Case of DischargedBattery............................56
45
46
52
53
48
5258
62
62
57
47
55
55
55
53
62
SPECIAL TOOLS ..__.......___..........................................................General Specifications
........................................................Lubricants............................................................................Sealants and Adhesives........................................................Service Specifications........................................................3
TROUBLESHOOTING............................................................5
WHEEL SPEED SENSOR (ABS)............................................88
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
(1)A Supplemental Restraint System (SRS), which uses a driver-side air bag, has been installed in the 3000GT.(2)The SRS includes the following components: impact sensors, SRS diagnosis unit: SRS warning light, air bagmodule, clock spring, interconnecting wiring. Other SRS-related components (that may have to be
removed/installed in connection with SRS service or maintenance) are indicated in the table of contents byan asterisk (*).
WARNING!(1)Improper service or maintenance of any component of the SRS, or any SRS-related component, can lead to
personal injury or death to service personnel (from inadvertent firing of the air bag) or to the driver (fromrendering the SRS inoperative).
(2) Service or maintenance of any SRS component or SRS-related component must be performed only at anauthorized MITSUBISHI dealer.
(3) MITSUBISHI dealer personnel must thoroughly review this manual, and especially its GROUP 52B
-Supplemental Restraint System (SRS), before beginning any service or maintenance of any component of theSRS or any SRS-related component.
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35-2SERVICE BRAKES - Specifications
SPECIFICATIONSrvKwx.- -
GENERAL SPECIFICATIONSItems
FWDAWD
Master cylinderTypeTandem type
(with level sensor)Tandem type
(with level sensor)
I.D. mm (in.)
25.4
(1) or 26.9 (1 %s)*26.9 (1 '/l6)Brake boosterTypeVacuum type, tandemVacuum type, tandem
Effective dia. of power cylinder
mm (in.)
180 (7.0) + 205 (8.0) or203 (8.0) + 230 (9.0)
203 (8.0) + 230 (9.0)”
Boosting ratio
6.0 [at 247 N (54
Ibs.)] or7.0
[Brake pedal depressing force]
7.0 [at 261 N (58 Ibs.)]”[at 261 N (58 Ibs.)]Proportioning valve
Split point
MPa (psi)3.75 - 4.25 (533 - 604)3.75 - 4.25 (533 - 604)
Decompression ratio
0.370.37
Front brakesTypeFloating caliper, 2-piston,Rigid caliper, 4-piston,
ventilated disc (M-R57W)ventilated disc
(M-R66Z)Disc effective dia.mm (in.)
227
(9.0)249 (9.8)Disc thickness
mm (in.)24
(.94)30 (1.18)
Pad thicknessmm (in.)
16 (.63)15 l.59)
Wheel cylinder I.D.mm (in.)
42.8(1"/16)X240.4(1'g/32)x2 +42.8(1"/16)~2
Clearance adjustment
AutomaticAutomatic
Rear brakesTypeFloating caliper, l-piston,
ventilated disc
(M-R45V)Floating caliper, 1 -piston,
ventilated disc (M-R58V)Disc effective dia.mm (in.)
228
(9.0)237 (9.4)Disc thicknessmm (in.)
18 (.71)20 (.79)Pad thickness
mm (in.)15.5
(.61)15.5 (.61)Wheel cylinder I.D.mm (in.)
34.9 (13/8)38.1 (1%)
Clearance adjustmentAutomaticAutomatic
Rotor teeth
Front wheel side
4747Rear wheel side
4747Speed sensor
Magnet coil typeMagnet coil type
NOTE*:ABS
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SERVICE BRAKES - Specifications
SERVICE SPECIFICATIONS
3msFWDAWD
andard value
Brake pedal heightmm (in.)
177 - 182 (7.0 - 7.2)
177 - 182 (7.0 - 7.2)Brake pedal free playmm (in.)
3-8(.1 -.3)3-8(.1 -.3)Brake pedal to floorboard clearance
mm (in.)
80 (3.1) or more
80 (3.1) or more
Pad thicknessmm (in.)
10.0 (.39)10.0 (.39)Front disc thickness
mm (in.)
24.0
t.94)30.0 (1.18)
Rear disc thickness
mm (in.)
18.0 (71)
20.0 (.79)Proportioning valve pressure
MPa (psi)
Split point
3.75 - 4.25 (533 - 604)3.75 - 4.25 (533 - 604)
Output pressure [input pressure]
5.23 - 5.73 (744 - 815)f8.0 (I, 138)]5.23 - 5.73 (744- 815)18.0 (1,138)]Booster
push;; (To,,;?aster cylinder piston
clearance
7
+ 8 inch brake booster
0.55 - 0.75 (.022 - ,030)-8 + 9 inch brake booster
0.65
- 0.85 (.026 - ,033)0.65 - 0.85 (026 - ,033)Disc brake drag force (tangential force of
wheel mounting bolts)
N (Ibs.)70 (15.4) or less
70 (15.4) or less
[Disc brake dragging torque[Nm (ft.lbs.)]
[4 (3) or less][4 (3) or less]
Speed sensor’s (ABS) internal resistance
kQFront
1.4-2.2
0.8 - 1.2
Rear1.3-2.1
0.8- 1.2
Rear speed sensor pole piece-to-rotor
tooth surface clearancemm (in.)
-28.15-28.45(1.11 -1.12)
Clearance between the
spmefm;l[yle piece
and the toothed rotor
Front0.3 - 0.9 (.012 - ,035)-
Rear0.2 - 0.7 (008 - .028)-nit
Left/right proportioning valve output
pressure difference
MPa (psi)0.4 (57)
0.4 (57)Front disc run-outmm (in.)
0.1
(.004) or less
0.1 (.004) or less
Pad thicknessmm (in.)
2.0
(08)2.0 (08)Front disc thicknessmm (in.)
22.4
(.88)28.4 (1.12)Front hub end playmm (in.)
0.05
(.002)0.05 (.002)Rear disc thicknessmm (in.)
16.4
(65)18.4 (.72)Rear disc run-outmm (in.)
0.08
(0031) or less
0.08 (.0031) or less
Rear hub end playmm (in.)
0.05
(002)0.8 (.031)
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35-4LUBRICANTSItems
Brake fluid
SERVICE BRAKES - Specifications / Special ToolsSpecified lubricant
Conforming to DOT3
M3!3xh~
dInside of shim A and shim B, or inside of inner shim A,
inner shim B, and outer shimBrake grease SAE J310,
NLGI No.1Guide pin and lock pin sliding part
Piston boot inner surface
Pin boot inner surfaceRepair kit grease
SEALANTS AND ADHESIVESM3S.X..
Items
Thread part fittingSpecified sealant
3M ATD Part No.8663 or equivalent
SPECIAL TOOLSM35DA- _MB991 359
MB991 377Adapter harness
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SERVICE BRAKES - Special Tools / TroubleshootingTROUBLESHOOTING
MJSEAASSymptomProbable cause
Remedy
Vehicle pulls to oneGrease or oil on pad or lining surface
Replace
side when brakes are
appliedInadequate contact of pad
Correct
Auto adjuster malfunction
Adjust
Insufficient brakingLow or deteriorated brake fluidAdd or refill
power
Air in brakesystemBleed air
Overheated brake rotor due to dragging of padCorrect
Grease or oil on pad surfaceReplace
Inadequate contact of padCorrect
Brake booster malfunctionCorrect
Auto adjuster malfunctionAdjust
Clogged brake lineCorrect
Proportioning valve malfunctionReplace
Increased pedal strokeAir in brake systemBleed air
(Reduced pedal to
floorboard clearance)Worn padReplace
Broken vacuum hoseReplace
Brake fluid leaksCorrect
Excessive push rod to master cylinder clearanceAdjust
Faulty master cylinderReplace
Brake dragWorn brake pedal return springReplace
Insufficient push rod to master cylinder clearanceAdjust
Defective master cylinder piston return springReplace
Clogged master cylinder return portCorrect
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35-6SERVICE BRAKES - TroubleshootingSymptomProbable cause
Remedy
Insufficient parking
Worn brake pad
brake functionReplace
Excessive parking brake lever stroke
Adjust the parking brake lever stroke
or check the parking brake cable
routing
Grease or oil on pad surface
Replace
Parking brake cable sticking
Replace
Stuck caliper piston
Replace
Scraping or grindingWorn brake pad
noise when brakes areReplace
appliedCaliper to wheel interferenceCorrect or replace
Cracked brake discCorrect or replace
Squealing, groaning or
chattering noise whenDisc brakes
- missing or damaged brake pad
anti-squeak shimReplace
brakes are applied
Brake discs and pads worn or scoredCorrect or replace
Improper lining partsCorrect or replace
Disc brakes-burred or rusted calipersClean or deburr
Dirty, greased, contaminated or glazed padClean or replace
Incorrect adjustment of brake pedal or booster
push-rodAdjust
Squealing noise whenDisc brakes
- rusted, stuck
brakes are not appliedLubricate or replace
Loose or extra parts in brakesRetighten
Improper positioning of pads in caliperCorrect
Improper installation of support mounting toCorrect
caliper body
Poor return of brake booster or master cylinderReplace
Incorrect adjustment of brake pedal or booster
push-rodAdjust
Groaning, clicking orStones or foreign material trapped inside wheelRemove stones, etc.
rattling noise whencovers
brakes are not applied
Loose wheel nutsRetighten
Disc brakes-failure of shimReplace
Disc brakes
- loose installation boltRetighten
Incorrect adjustment of brake pedal or booster
push-rodAdjust
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SERVICE BRAKES -Anti-lock Braking System Troubleshooting35-7
ANTI-LOCK BRAKING SYSTEM TROUBLESHOOTlilGPARTICULAR PHENOMENA OF THE
LANTI-LOCK BRAKING SYSTEMModels equipped with the anti-lock braking system
(ABS) may exhibit one or more of the following
phenomena from time to time, but none of these
are abnormal.
(1) A pulsing feeling in the brake pedal, or vibration
of the body or the steering wheel, when the
anti-lock braking system is activated by sudden
braking or by braking on a slippery road surface.
.9ctually, this phenomenon is an indication that
the anti-lock braking system is functioning nor-
mally.(2) When the vehicle speed reaches approximately
6 km/h (4 mph) after the engine is started and
the vehicle starts off (for the first time), a
whining motor noise may be heard from the
engine compartment if the vehicle is traveling in
a quiet place, but this noise is simply the result
of a self-check being made of the anti-lock
braking system operation.
TROUBLESHOOTING METHODSProblems related to the anti-lock braking system
(ABS) can be classified into two general categories:
problems in the electrical system and those in the
Lhydraulic system.For problems in the electrical system, the
self-diagnosis function is built into the electronic control
unit (E.C.U.) causing the ABS warning light to
illuminate as a warning to the driver. In this instance,
checks can be made by using the multi-use tester
and oscilloscope.
Problems in the hydraulic system (poor braking,
etc.) can be located in the same way as for ordinary
brakes. There is, however, the necessity to check to
determine whether the problem is related to ordin-
ary brake components or to the components related
to the ABS. To make this check, use the multi-use
tester.
HOW TO USE THE TROUBLESHOOTING
FLOW CHART(1) Using the flow chart, check the ABS warning
light light-up sequence. Read the diagnosis
codes and check the condition of braking opera-
tion.
(2) Following the check chart listed in the remedy
column, perform the checks. There are [Explana-
tion] and [Hint] in each check chart. Refer to
them when troubleshooting.
NOTEECU: Electronic control unit
HU: Hydraulic unit
MUT: Multi-use tester
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35-8SERVICE BRAKES -Anti-lock Braking System Troubleshooting
TROUBLESHOOTING (ABS - FWD)Confirm condition in the following way and diagnosis accordingly.
Does the ABS warning light illuminate as described
(2) With the ignition key in the “START” position,
below up to the time the engine starts?power to the ABS ECU is interrupted and the
(1) When the ignition key is turned to the “ON”ABS warning light remains lit because the valve
position, the ABS ECU causes the ABS warningrelay is OFF.
light to flash twice in about one second (during
(3) When the ignition key is returned from the
which the valve relay self check is made) and“START” position to the “ON” position, the
then causes it to go out.ABS warning light flashes twice in about one
second (during which. the valve relay self check
-is made again) and then goes out.
ABS warning
ONlightII
-I
keyACC,
LO!: +--14A0589
Yes>CONTINUED ON NEXT PAGE
No
”
weenABS warning
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SERVICE BRAKES -Anti-lock Braking System Troubleshooting
L’
No.Trouble condition\4
After the ignition key is turned to the
“ON” position, it blinks once and then
illuminates when it is turned to the
“START” position. When the key is
returned to the “ON” position, the light
blinks again. (Blinking with the ignition
key in the “ON” position is synchronized
with operation noise of the valve relay.)
ABSwarninglight
key ACC. L::+
Ignition
14A05931 CONTINUED FROM PREVIOUS PAGE
1Major causes
l Break in harness for ECU warning
light drive circuit
l Malfunction of ECU
Does the ABS warning light illuminate
when starting to drive the car?
iIs there one-sided braking, insufficient
>CONTINUED ON NEXT PAGEI
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YesTrouble condition
One-sided braking
Insufficient braking force
ABS sometimes functions even when
there is no sudden braking.
(ABSoperation vibration is transmitted.)Remedy
Check, using flow
P.35-19.)Remedy
l Check HU operation and, if
l necessary, replace HU.
If HU is normal, check struc-
l
HydraJicl Malfunction in HU solenoid valvetural parts for normal
braking.
Insufficient wheel speed sensor put voltage (sensor malfunction, too
large a gap between sensor rotor,
l Malfunction of ABS ECU(Refer to
P.35-57.) and, if
necessary, replace sensor,
If tests indicate that there are
no mechanical or electricalfaiIures,replace the ECU.
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35-10SERVICE BRAKES -Anti-lock Braking System Troubleshooting
j CONTINUED FROM PREVIOUS PAGE /After a test drive, use self-diagnosis to
P.35-11.).>
1No trouble codes output and normal
codes are displayed?
NoTrouble codes are output
Yes
All ABS functions are normal.
(Nor are there stored memory of
past trouble code.)put terminals and the di-
agnosis check connector.
If trouble does not re-
appear, watch vehicle
movements until it reap-
pears. (Refer to
P.35-12.)
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