1997 MITSUBISHI TRITON brakes

MPI ± Troubleshooting13A-57
DATA LIST REFERENCE TABLE13100890180
Caution
When shifting the select lever to D range, the brakes should be applied so that the vehicle does
not move forward.
NOTE
*1. In a new vehicle [driven approximately 500 km or less], the air flow sensor output frequency is sometimes
10% higher than the standard frequency.
*
2. The idle position switch normally turns off when the voltage of the throttle position sensor is 50 ±
100 mV higher than the voltage at the idle position. If the idle position switch turns back on after
the throttle position sensor voltage has been by 100 mV and the throttle valve has been opened,
the idle position switch and the throttle position sensor need to be adjusted.
*3. The injector drive time represents the time when the cranking speed is at 250 r/min or below when
the power supply voltage is 11 V.
*4. In a new vehicle [driven approximately 500 km or less], the injector drive time is sometimes 10%
longer than the standard time.
*5. In a new vehicle [driven approximately 500 km or less], the step of the stepper motor is sometimes
30 steps greater than the standard value.
Item
No.Inspection
itemInspection contentsNormal conditionInspection
procedure
No.Reference
page
11Oxygen
sensorEngine:After having
warmed up
Air/fuel mixture is
made leaner when de-
When at 4,000 r/min,
engine is suddenly
decelerated200 mV or lessCode No.
1113A-11
made leaner when de-
celerating, and is made
richer when racing.
When engine is
suddenly raced600 ± 1,000 mV
Engine:After having
warmed up
The oxygen sensor
signal is used to check
the air/fuel mixture
ratio and control
Engine is idling400 mV or less
(Changes)
600 ± 1,000 mV
ratio, and control
condition by the en-
gine-ECU.2,500 r/min400 mV or less
(Changes)
600 ± 1,000 mV
12Air flow
sensor*1
Engine coolant
temperature:
80 ± 95C

Lamps and all
accessories: OFF
Engine is idling22 ± 48 Hz
<4G63>
19 ± 45 Hz
<4G64>±±
accessories: OFF

Transmission:
Neutral (A/T:
P range)2,500 r/min80 ± 120 Hz
<4G63>
67 ± 107 Hz
<4G64>
Engine is racedFrequency
increases in
response to
racing

AUTOMATIC TRANSMISSION ± Troubleshooting23-7
2 RANGE TEST
Correct
Carry out TEST 1 again.
Ye s
Check the shifting point.Incorrect
Misadjusted throttle cable

Governor malfunction

Line pressure malfunction
No
Does the upshift from 1-speed to 2-speed occur?No
1 ± 2 shift valve malfunction

Governor malfunction
TEST 1
Start with throttle valve opening at 50% and full. Does the shifting
points conform with the shift pattern when upshifting from 1-speed

2-speed?Ye sTEST 2
Ye s
Carry out TEST 2 again.
NG
Does the downshift occur and is the shifting point correct?No
Detent regulator valve malfunction

Governor malfunction

Misadjusted throttle cable

1 ± 2 shift valve malfunction

Line pressure malfunction
TEST 2
Kickdown and check that possible kickdown vehicle speed limit
at 2-speed
1-speed conforms with shift pattern.OKCarry out road test in L range.
L RANGE TEST
No
Carry out road test in R range.
TEST 1
Does the transmission upshift to 2-speed?Ye s
Low coast modulator valve malfunction

Governor malfunction

Low line pressure
R RANGE TEST
Ye s
Carry out road test in P range.
TEST 1
Is the engine r/min by stall test correct?No
Brake No. 3 malfunction

Overdrive clutch or direct clutch malfunction

Overdrive one-way clutch malfunction

Low line pressure
P RANGE TEST
Ye s
End
TEST 1
Park vehicle on an incline (more than 5) and release parking
and service brakes. Does the vehicle move?No
Park mechanism malfunction

Misadjusted shift lever

AUTOMATIC TRANSMISSION ± On-vehicle Service23-19
CONVERTER STALL TEST 23100540138
In this test, the engine maximum speed when the
torque converter stalls with the shift lever in the
ªDº or ªRº range is measured to check operation
of the torque converter, starter and one-way clutch
and check holding performance of the transmission
clutch (including brake).
Caution
Do not stand in front or at rear of the vehicle
during this test.
(1) Check the transmission fluid level. The fluid
temperature should be at the level after normal
operation (70 ± 80
C). The engine coolant
temperature should also be at the level after
normal operation (80 ± 90
C).
(2) Apply chocks to the rear wheels (right and left).
(3) Mount an engine tachometer.
(4) Apply fully the parking and service brakes.(5) Start the engine.
(6) With the selector lever in the ªDº range, fully
depress the accelerator pedal and read off the
engine maximum speed.
Standard value:
2,100 ± 2,400 r/min <4G63>
2,300 ± 2,600 r/min <4D56>
NOTE
When doing so, do not keep the engine running
with throttle full open for more than 5 seconds.
If two or more stall tests are needed, place
the selector lever in the ªNº position and run
the engine at about 1,000 r/min to allow the
transmission fluid to cool before another stall
test.
(7) Place the selector lever in the ªRº range and
perform the test as above.
JUDGEMENT OF STALL TEST RESULTS
Stall speed in ªDº and ªRº range is equal to each other
but lower than the nominal value.(1) Engine output is low.
(2) Starter one-way clutch is faulty. (Faulty torque
converter is suspected if it is lower than nominal
by more than 600 r/min)
Stall speed in ªDº range is higher than nominal.(1) Overdrive clutch slipping
(2) Overdrive one-way clutch faulty
(3) Forward clutch slipping
(4) One-way clutch No. 2 faulty
(5) Low line pressure
Stall speed in ªRº range is higher than nominal.(1) Overdrive clutch slipping
(2) Overdrive one-way clutch faulty
(3) Direct clutch slipping
(4) Brake No. 3 slipping
(5) Low line pressure

BASIC BRAKE SYSTEM ± General Information35A-3
GENERAL INFORMATION35100010120
The brake system has high reliability and durability
which maintains excellent braking performance and
braking feeling. The main features are as follows.

A dual type master cylinder is equipped in all
models.

Both a single type and a tandem type brake
booster have been adopted.
The following type of brake have been adopted.
Front: Floating caliper, 2-piston, ventilated disc
brakes (V4-W43, V5-W43) or floating caliper,
1-piston, ventilated disc brakes (V4-S60,
V5-S60)
Rear: Leading-trailing type drum brake.
Items2WD
vehicles>2WD
vehicles>4WD
vehicles>4WD
vehicles>
Master cylinder I.D. mm23.823.823.823.8
Brake booster effective dia.
of power cylinder mm230
205 + 230*230
180 + 205*205 + 230180 + 205
Brake booster boosting ratio5.05.07.07.0
Load sensing proportioning
valve decompression ratio0.150.150.150.15
Front brake disc effective
dia. mm200200222
228*222
228*
Front brake wheel cylinder
I.D. mm60.3
42.9*60.3
42.9*60.3
42.9*60.3
42.9*
Rear drum brake drum I.D.
mm254254270270
Rear drum brake wheel
cylinder I.D. mm23.823.823.823.8
Rear drum brake lining
thickness mm4.74.74.74.7
NOTE
*: Vehicles with ABS.

BASIC BRAKE SYSTEM ± Troubleshooting35A-7
TROUBLESHOOTING35100070081
SymptomProbable causeRemedy
Vehicle pulls to one side
when brakes are applied
Grease or oil on pad or lining surfaceReplace
when brakes are a lied
Inadequate contact of pad or liningCorrect
Auto adjuster malfunctionAdjust
Drum eccentricity or uneven wearRepair or replace as necessary
Insufficient braking powerLow or deteriorated brake fluidRefill or change
Air in brake systemBleed air
Overheated brake rotor due to dragging of pad
or liningCorrect
Inadequate contact of pad or lining
Brake booster malfunction
Clogged brake line
Grease or oil on pad or lining surfaceReplace
Load sensing proportioning valve malfunction
Auto adjuster malfunctionAdjust
Increased pedal stroke
(Reducedpedal to floor
Air in brake systemBleed air
(Reduced edal to floor
board clearance)Worn lining or padReplace
Broken vacuum hose
Faulty master cylinder
Brake fluid leaksCorrect
Auto adjuster malfunctionAdjust
Excessive push rod to master cylinder
clearance
Brake dragIncomplete release of parking brakeCorrect
Clogged master cylinder return port
Incorrect parking brake adjustmentAdjust
Improper push rod to master cylinder
clearance
Faulty master cylinder piston return springReplace
Worn brake pedal return spring
Broken rear drum brake shoe to shoe spring
Lack of lubrication in sliding partsLubricate

BASIC BRAKE SYSTEM ± Troubleshooting35A-8
SymptomProbable causeRemedy
Insufficient parking brake functionWorn brake lining or padReplace
Grease or oil on lining or pad surface
Parking brake cable sticking
Stuck wheel cylinder or caliper piston
Excessive parking brake lever strokeAdjust the parking brake lever stroke or
check the parking brake cable routing
Auto adjuster malfunctionAdjust
Scraping or grinding noise when
brakes are applied
Worn brake lining or padReplace
brakes are a lied
Caliper to wheel interferenceCorrect or replace
Dust cover to disc interference
Bent brake backing plate
Cracked drums or brake disc
Squealing, groaning or chattering
noise when brakes are appliedDisc brakes ± Missing or damaged
brake pad anti-squeak shimReplace
Brake drums and linings, discs and pads
worn or scoredCorrect or replace
Improper lining parts
Disc brake ± Burred or rusted calipersCorrect or deburr
Dirty, greased, contaminated or glazed
liningsClean or replace
Drum brakes ± Weak, damaged or
incorrect shoe hold-down springs, loose
or damaged shoe hold-down pins and
springsCorrect or replace
Incorrect brake pedal or booster push rodAdjust

BASIC BRAKE SYSTEM ± Troubleshooting35A-9
SymptomProbable causeRemedy
Squealing noise
when brakes are
Bent or warped backing plate causing interference with drumReplace
when brakes are
not appliedDrum brakes ± Weak, damaged or incorrect shoe-to-shoe
spring
Poor return of brake booster, master cylinder or wheel
cylinder
Loose or extra parts in brakesRetighten
Improper positioning of pads in caliperCorrect
Improper installation of support mounting to caliper body
Improper machining of drum causing interference with
backing plate or shoeReplace drum
Disc brakes ± Rusted, stuckLubricate or replace
Worn, damaged or insufficiently lubricated wheel bearings
Incorrect brake pedal or booster push rodAdjust
Groaning, clicking or
rattling noise when
Stones or foreign material trapped inside wheel coversRemove stones, etc.
rattling noise when
brakes are not appliedLoose wheel nutsRetighten
Disc brakes ± Loose installation bolts
Worn, damaged or dry wheel bearingsLubricate or replace
Disc brakes ± Failure of shimReplace
Disc brakes ± Wear on sleeve
Incorrect brake pedal or booster push rodAdjust

54-3
REAR WINDOW DEFOGGER 83. . . . . . .
SPECIAL TOOL 83. . . . . . . . . . . . . . . . . . . . . . . .
ON-VEHICLE SERVICE 83. . . . . . . . . . . . . . . . .
Printed-heater Line Check 83. . . . . . . . . . . . . . . .
REAR WINDOW DEFOGGER SWITCH 84. . .
RADIATOR FAN MOTOR
Refer to GROUP 14 . . . . . . . . . . . . . . . . . . .
INTERCOOLER (INTERCOOLER FAN
MOTOR) Refer to GROUP 15. . . . . . . . . .
REAR DIFFERENTIAL LOCK
Refer to GROUP 27 . . . . . . . . . . . . . . . . . . .
SERVICE BRAKES (ABS)
Refer to GROUP 35B, 35C . . . . . . . . . . . .
DOOR GLASS AND REGULATOR
(POWER WINDOWS)
Refer to GROUP 42 . . . . . . . . . . . . . . . . . . . DOOR HANDLE AND LATCH (DOOR
LOCKING) Refer to GROUP 42. . . . . . . .
WINDSHIELD WIPER AND WASHER
Refer to GROUP 51 . . . . . . . . . . . . . . . . . . .
HEADLAMP WASHER
Refer to GROUP 51 . . . . . . . . . . . . . . . . . . .
DOOR MIRROR (ELECTRONIC
CONTROLLED DOOR MIRROR)
Refer to GROUP 51 . . . . . . . . . . . . . . . . . . .
FRONT SEAT (HEATED SEAT)
Refer to GROUP 52A . . . . . . . . . . . . . . . . .
SRS AIR BAG
Refer to GROUP 52B . . . . . . . . . . . . . . . . .
HEATER Refer to GROUP 55. . . . . . . . . .
AIR CONDITIONER
Refer to GROUP 55 . . . . . . . . . . . . . . . . . . .