light MITSUBISHI MONTERO 1998 Owner's Manual
[x] Cancel search | Manufacturer: MITSUBISHI, Model Year: 1998, Model line: MONTERO, Model: MITSUBISHI MONTERO 1998Pages: 1501, PDF Size: 25.81 MB
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ANTI-LOCK BRAKE SYSTEM
1998 Mitsubishi Montero
1997-98 BRAKES
Mitsubishi - Anti-Lock
Montero
DESCRIPTION
CAUTION: See ANTI-LOCK BRAKE SAFETY PRECAUTIONS article in GENERAL
INFORMATION.
NOTE: For more information on brake system, see BRAKE SYSTEM
article.
The Anti-Lock Brake System (ABS) is designed to prevent wheel\
lock-up during heavy braking. This allows operator to maintain
steering control while stopping vehicle in shortest distance possible.
Major components are a hydraulic unit, wheel speed sensors, "G"
sensor, ABS Electronic Control Unit (ECU) and ANTI-LOCK warning light.\
ABS has a self-diagnostic system to indicate a system malfunction and
for use in system trouble shooting.
OPERATION
Each wheel sensor sends an AC electrical signal to the ECU.
The ECU reads this information as wheel speed. When any decelerating
wheel speed rate is determined to be excessive in comparison to other
monitored wheels, the hydraulic unit cycles hydraulic brake pressure
to each wheel to equalize speed of all wheels. ABS turns itself off
when vehicle drops to 4 MPH. Minor lock-up may occur at this point.
With engine running and vehicle speed greater than 4 MPH,
pump motor will operate for a short period of time and may be heard
inside vehicle. During pump motor operation, ABS system is completing
a self-check. During ABS system operation, a pulsing brake pedal and
vibration in steering wheel and vehicle body may be experienced. These
conditions are normal.
BLEEDING BRAKE SYSTEM
BLEEDING PROCEDURES
CAUTION: When adding brake fluid, ensure filter is properly fitted on
reservoir tank.
ABS system is bled using conventional method. With engine
running, manually bleed system using an assistant. For bleeding order,
see BRAKE LINE BLEEDING SEQUENCE table. Ensure Load Sensing
Proportioning Valve (LSPV) is bled in sequence. Remove all air from
brake system. Refill brake fluid reservoir after bleeding procedure is
complete.
BRAKE LINE BLEEDING SEQUENCE
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Application Sequence
Montero ....................................... RR, LR, LSPV, RF, LF
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ADJUSTMENTS
* PLEASE READ FIRST *
NOTE: For adjustment information on brake pedal height, free play,
parking brake and stoplight switch, see BRAKE SYSTEM article.
WHEEL SPEED SENSOR (WSS)
NOTE: Rear WSS gap adjustment information is not available from
manufacturer.
Front WSS-To-Rotor Gap Adjustment
1) Raise and support vehicle. Remove wheel(s). Inspect senso\
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pole piece for damage. Repair if necessary. If sensor pole piece is
okay, check WSS-to-rotor gap.
2) Using a feeler gauge, check clearance between sensor pole
and rotor tooth surface. See Fig. 1. Front WSS sensor clearance should
be .008-.390" (0.2-1.0 mm). If clearance is not as specified, loosen
sensor mounting bolt. Adjust sensor position until clearance is within
specification. Tighten sensor mounting bolt to specification. See
TORQUE SPECIFICATIONS .
Fig. 1: Checking Front WSS-To-Rotor Gap
Courtesy of Mitsubishi Motor Sales of America.
TROUBLE SHOOTING
ANTI-LOCK WARNING LIGHT
1) Turn ignition on. ANTI-LOCK warning light should come on
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for one second, and then go out. Turn ignition switch to START
position. Warning light should come on and stay on.
2) When ignition switch is turned from START to ON position,
warning light should come on for one second, and then go out. If
warning light functions as specified, go to step 3). If warning light
does not function as specified, see appropriate trouble shooting test:
* IGNITION SWITCH IN ON POSITION (ENGINE NOT RUNNING),
ANTI-LOCK WARNING LIGHT INOPERATIVE
* AFTER ENGINE STARTS, ANTI-LOCK WARNING LIGHT REMAINS ON
* IGNITION SWITCH IN START POSITION, ANTI-LOCK WARNING LIGHT
INOPERATIVE
* IGNITION SWITCH IN ON POSITION, ANTI-LOCK WARNING LIGHT
BLINKS TWICE. IN START POSITION, LIGHT STAYS ON. WHEN
IGNITION SWITCH IS CYCLED FROM START TO ON POSITION, LIGHT
BLINKS ONCE, THEN TURNS OFF
3) Test drive vehicle. If ANTI-LOCK warning light does not
come on at low speed, go to next step. If light comes on at low speed,
motor relay, solenoid valve or Wheel Speed Sensor (WSS) malfunction is\
indicated. Go to step 6). If insufficient braking force or ABS
malfunction exists, go to next step. If none of listed symptoms exist,
go to step 6).
4) Check conventional brake system components for proper
operation. Check for mechanical lock of hydraulic unit solenoid valve.
Check for plugged hydraulic line in hydraulic unit. Repair or replace
as necessary. If hydraulic unit is okay, go to next step.
5) Ensure WSS rotor gap is correct. See WHEEL SPEED SENSOR
(WSS) under ADJUSTMENTS. Check for faulty wheel speed sensor. See
WHEEL SPEED SENSOR (WSS) under COMPONENT TESTS. Replace sensor as
necessary. See WHEEL SPEED SENSOR (WSS) under REMOVAL & INSTALLATION.
Inspect ECU connectors and related wiring harness. See WIRING DIAGRAMS
. If testing indicates no mechanical or electrical failures,
substitute ECU with known-good unit and retest.
6) Enter ABS self-diagnostics and retrieve Diagnostic Trouble
Codes (DTCs). See RETRIEVING DTCs under SELF-DIAGNOSTIC SYSTEM. If no
DTCs are displayed, fault may be intermittent. Attempt to make
malfunction reoccur. If no diagnostic output exists, check and repair
wiring harness between ECU and data link connector. See
WIRING DIAGRAMS .
NOTE: Trouble shoot ANTI-LOCK warning light in following sequence:
instrument cluster circuit, ECU and valve relay.
Ignition Switch In ON position (Engine Not Running),
ANTI-LOCK Warning Light Inoperative
1) If all other warning lights come on with ignition on, go
to step 3). If other warning lights do not come on, check fuse No. 11
in main fuse panel. If fuse is blown, correct cause of blown fuse, and
replace fuse. If fuse is okay, go to next step.
2) Remove instrument cluster. Turn ignition on. Using DVOM,
check voltage between vehicle ground and instrument cluster ANTI-LOCK
warning light terminal No. 28. See Fig. 2. If light does not come on,
go to next step. If light comes on, check and repair connectors and
related wiring harness between instrument cluster, ABS valve relay and
ECU. See WIRING DIAGRAMS .
3) Turn ignition off. Check for faulty warning light bulb.
Replace bulb as necessary. If bulb is okay, check and repair
connectors and related wiring harness between instrument cluster and
ECU. See WIRING DIAGRAMS . If connectors and wiring are okay, replace
instrument cluster.
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Fig. 2: Identifying Instrument Cluster Connector Terminals
Courtesy of Mitsubishi Motor Sales of America.
After Engine Starts, ANTI-LOCK Warning Light Remains On
1) With ignition on, disconnect instrument cluster
connectors. If warning light remains on, replace instrument cluster.
If warning light goes off, go to next step.
2) Disconnect ECU 22-pin connector and ABS relay box 8-pin
connector. See Fig. 3. If warning light goes off, replace ECU. If
warning light stays on, check and repair connectors and related wiring
harness between ECU, instrument cluster, and ABS valve relay. See
WIRING DIAGRAMS .
Fig. 3: Exploded View Of Hydraulic Unit & Components
Courtesy of Mitsubishi Motor Sales of America.
Ignition Switch In START Position, ANTI-LOCK Warning Light
Inoperative
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1) Inspect ABS relay box. See Fig. 3. Replace ABS relay box
if needed. If ABS relay box is okay, go to next step.
2) Disconnect ECU 22-pin connector and ABS relay box 8-pin
connector. Turn ignition on. Using a DVOM, check voltage between ABS
relay box 8-pin harness connector terminal No. 5 and ground. See
Fig. 4 . If battery voltage does not exist, go to next step. If battery
voltage exists, check and repair connectors and related wiring harness
between ABS valve relay and ground. See WIRING DIAGRAMS.
3) Check and repair connectors and related wiring harness
between instrument cluster and ABS valve relay. See WIRING DIAGRAMS.
Fig. 4: Identifying ABS Relay Box Connector Terminals
Courtesy of Mitsubishi Motor Sales of America.
Ignition Switch In ON Position, ANTI-LOCK Warning Light
Blinks Twice. In START Position, Light Stays On. When
Ignition Switch Is Cycled From START To ON Position, Light
Blinks Once
1) Disconnect ABS relay box connectors. See Fig. 3.
Disconnect ECU 22-pin connector. Turn ignition on. Check voltage
between ECU connector terminal No. 50 and ground. See Figs. 5-6. If
battery voltage is not present, check and repair connectors and
related wiring harness between instrument cluster and ECU. See
WIRING DIAGRAMS . If battery voltage is present, go to next step.
2) Check and repair ECU 22-pin connector. If connector is
okay, replace ECU.
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Fig. 5: Identifying ECU Harness Connector Terminals 22-Pin Connector
Courtesy of Mitsubishi Motor Sales of America.
Fig. 6: Identifying ECU Harness Connector Terminals 26-Pin Connector
Courtesy of Mitsubishi Motor Sales of America.
SELF-DIAGNOSTIC SYSTEM
RETRIEVING DTCs
Using Scan Tool
1) With ignition off, connect scan tool and ROM Pack to Data
Link Connector (DLC) located under driver's side of dash, and to
cigarette lighter socket. See Fig. 7.
2) Turn ignition on. ANTI-LOCK warning light should come on
as ABS goes into self-diagnostic mode. Read and record all Diagnostic
Trouble Codes (DTCs) from ECU memory. Refer to scan tool
manufacturer's instructions for specific DTC retrieval procedure.
3) After all of the DTCs have been retrieved and recorded,
clear codes from ECU memory. Refer to scan tool manufacturer's
instructions for specific DTC clearing instructions. Refer to DTC
DEFINITION under SELF-DIAGNOSTIC SYSTEM . Refer to the appropriate DTC
under DIAGNOSTIC TESTS .
4) If DTCs cannot be cleared, ECU is currently detecting a
malfunction. If codes can be cleared, problem is either intermittent
or only appears while driving.
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Fig. 7: Connecting Scan Tool
Courtesy of Mitsubishi Motor Sales of America.
Using ANTI-LOCK Warning Light
1) To retrieve stored DTCs, locate Data Link Connector (DLC)\
under left side of dash. Turn ignition off. Ground DLC terminal No. 1.
See Fig. 8 .
2) If DTCs are stored in ECU memory, ANTI-LOCK light will
begin to flash intermittently. Long flashes represent first digit of
DTC; short flashes represent second digit. For example, 4 long flashes
and 3 short flashes indicate DTC 43. If 2 or more DTCs are stored,
lowest number will be displayed first. DTC 51 will always be displayed
if valve relay is removed.
3) After recording DTC(s), see DTC DEFINITION table and
perform appropriate DTC test(s) under DIAGNOSTIC TESTS. If no DTCs are
stored, ANTI-LOCK warning light will flash constantly.
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27 ..................... (3) Rear Differential Lock Detection Switch
32 ............................................... "G" Sensor System
33 ......................................... Stoplight Switch System
41 ....................................... RF Solenoid Valve Circuit
42 ....................................... LF Solenoid Valve Circuit
43 ..................................... Rear Solenoid Valve Circuit
51 ..................................................... Valve Relay
53 ..................................................... Motor Relay
63 Or 64 ............................................ ( 4) Faulty ECU
( 1) - See appropriate DTC under DIAGNOSTIC TESTS.
( 2) - Vehicles with differential lock.
( 3) - Vehicles without differential lock.
( 4) - Replace ECU.
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DIAGNOSTIC TESTS
DTC 11, 12, 13 OR 14: WHEEL SPEED SENSOR (OPEN/SHORT
CIRCUIT)
NOTE: DTC will set if ECU detects a wheel speed sensor open or
short circuit.
1) Ensure sensor is properly installed. See WHEEL SPEED
SENSOR (WSS) under REMOVAL & INSTALLATION . Correct installation if
needed. If installation is okay, go to next step.
2) Disconnect ECU 26-pin connector. Check resistance between
specified ECU connector terminals. See
WHEEL SPEED SENSOR OUTPUT CIRCUIT IDENTIFICATION table. See Figs. 5-6.
Resistance for front sensors should be 1170-1350 ohms. Resistance for
rear sensors should be 1300-1500 ohms. If resistance is as specified,
go to next step. If resistance is not as specified, check and repair
connectors and related wiring between ECU and suspect sensor. See
WIRING DIAGRAMS .
WHEEL SPEED SENSOR OUTPUT CIRCUIT IDENTIFICATION
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Application Terminals No.
Left Front .................................................. 7 & 20
Left Rear ................................................... 9 & 22
Right Front ................................................ 10 & 23
Right Rear .................................................. 8 & 21
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3) Raise and support vehicle. Disconnect ECU connectors.
Using DVOM, backprobe specified ECU connector terminals. See
WHEEL SPEED SENSOR OUTPUT CIRCUIT IDENTIFICATION table. See Figs. 5-6.
Check voltage between each harness connector terminal while rotating
wheel at 1/2 to one rotation per second. If pulse voltage is 70 mV or
more, go to step 8). If voltage is not as specified, go to next step.
4) Inspect condition of suspect speed sensor. Ensure tip of
speed sensor is clean. If speed sensor is okay, go to next step.
5) Disconnect sensor connector. Using DVOM, check resistance
across sensor terminals. Resistance for front sensors should be 1170-
1350 ohms. Resistance for rear sensors should be 1300-1500 ohms. If
resistance is as specified, go to next step. If resistance is not as
specified, replace sensor.
6) Remove sensor. Check resistance between each sensor
terminal and sensor body. If resistance is 100,000 ohms or more, go to
next step. If resistance is not as specified, replace sensor.
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2) Disconnect ECU 26-pin connector. Check resistance between
specified ECU connector terminals. See
WHEEL SPEED SENSOR OUTPUT CIRCUIT IDENTIFICATION table. See Figs. 5-6.
Resistance for front sensors should be 1170-1350 ohms. Resistance for
rear sensors should be 1300-1500 ohms. If resistance is as specified,
go to next step. If resistance is not as specified, check and repair
connectors and related wiring between ECU and suspect sensor. See
WIRING DIAGRAMS .
3) Raise and support vehicle. Disconnect ECU connectors.
Using DVOM, backprobe specified ECU connector terminals. See
WHEEL SPEED SENSOR OUTPUT CIRCUIT IDENTIFICATION table. See Figs. 5-6.
Check voltage between each harness connector terminal while rotating
wheel at 1/2 to one rotation per second. If pulse voltage is 70 mV or
more, go to step 8). If voltage is not as specified, go to next step.
4) Inspect condition of suspect speed sensor. Ensure tip of
speed sensor is clean. If speed sensor is okay, go to next step.
5) Disconnect sensor connector. Using DVOM, check resistance
across sensor terminals. Resistance for front sensors should be 1170-
1350 ohms. Resistance for rear sensors should be 1300-1500 ohms. If
resistance is as specified, go to next step. If resistance is not as
specified, replace sensor.
6) Remove sensor. Check resistance between each sensor
terminal and sensor body. If resistance is 100,000 ohms or more, go to
next step. If resistance is not as specified, replace sensor.
7) Inspect condition of toothed rotor. Check for broken or
deformed teeth. If toothed rotor is okay, go to next step.
8) Check ECU connectors. Repair connectors as needed. If
connectors are okay, replace ECU.
DTC 25: FREE WHEEL ENGAGE SWITCH
NOTE: DTC sets if ECU detects an open circuit in free wheel engage
switch.
1) Start engine. Ensure 4WD indicator light operates
correctly when transfer shift lever is moved to desired 4WD positions.
If indicator light operates correctly, go to step 3). If indicator
light does not operate correctly, go to next step.
2) Turn engine off. Check wiring harness between 4WD
indicator control unit (located behind radio) and free wheel engage
switch (located on right side of front differential housing, near
carrier assembly). If circuit is okay, replace 4WD indicator control
unit.
3) Disconnect ECU 22-pin connector. Turn ignition on. Using
DVOM, check voltage between ECU 22-pin connector terminal No. 45 and
ground. See Figs. 5-6. In 2WD, battery voltage should exist. Battery
voltage should not exist in 4WD. If voltage is as specified, go to
next step. If voltage is not as specified, check and repair connectors
and wiring harness between free wheel engage switch and ECU. See
WIRING DIAGRAMS .
4) Check and repair ECU 22-pin connector. If connector is
okay, replace ECU.
DTC 26: CENTER DIFFERENTIAL LOCK DETECTION SWITCH
NOTE: DTC sets if ECU detects an open circuit in center
differential lock detection switch system.
1) Start engine. Ensure 4WD indicator light operates
correctly when transfer shift lever is moved to desired 4WD positions.
If indicator light does not operate correctly, go to step 4). If
indicator light operates correctly, go to next step.
2) Disconnect ECU 22-pin connector. Turn ignition on. Using
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DVOM, check voltage between ECU 22-pin connector terminal No. 35 and
ground. See Figs. 5-6. Battery voltage should exist in 4WD. Go to next
step.
3) If voltage is not as specified, check and repair
connectors and wiring harness between center differential lock
detection switch and ECU. See WIRING DIAGRAMS. Center differential
lock detection switch is located on side of transfer case. See Fig. 9.
If voltage is as specified, check and repair ECU 22-pin connector. If
connector is okay, replace ECU.
Fig. 9: Identifying 4WD Indicator Switch Location
Courtesy of Mitsubishi Motor Sales of America.
NOTE: When checking for short in ECU circuit, remove ECU connector
and ensure 4WD indicator light operates correctly. If 4WD
indicator light operates correctly, replace faulty ECU. If
4WD indicator light does not operate correctly, replace
faulty 4WD indicator control unit.
4) If no indicator lights come on, repair 4WD indicator power
circuit, or check for faulty 4WD indicator control unit. See 4WD
CONTROL UNIT under COMPONENT TESTS. If center differential light comes
on, regardless of position of transfer shift lever, check the
following: