warning light MITSUBISHI MONTERO 1998 Service Manual
[x] Cancel search | Manufacturer: MITSUBISHI, Model Year: 1998, Model line: MONTERO, Model: MITSUBISHI MONTERO 1998Pages: 1501, PDF Size: 25.81 MB
Page 84 of 1501

A/C-HEATER SYSTEM
1998 Mitsubishi Montero
1998 AIR CONDITIONING & HEAT
Mitsubishi - A/C-Heater System
Montero
* PLEASE READ THIS FIRST *
WARNING: To avoid injury from accidental air bag deployment, read and
carefully follow all SERVICE PRECAUTIONS and DISABLING &
ACTIVATING AIR BAG SYSTEM procedures in AIR BAG RESTRAINT
SYSTEM article.
A/C SYSTEM SPECIFICATIONS
A/C SYSTEM SPECIFICATIONS TABLE \
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Application Specification
Compressor Type ............... Nippondenso 10PA15 10-Cyl.
Compressor Belt Deflection ( 1)
New .......................... 13/64-15/64" (5.1-6.0 mm)
Used ......................... 17/64-19/64" (6.6-7.5 mm)
Compressor Oil Capacity ..................... ( 2) 2.7 ozs.
Refrigerant (R-134a) Capacity ................. 21-23 ozs.
System Operating Pressures ( 4)
High Side ............... 149-213 psi (10.5-15.0 kg/cm
)
Low Side .................... 14-33 psi (1.0-2.3 kg/cm)
( 1) - With 22 lbs. (100 N.m) force applied midway on longest
span of belt.
( 2) - Use ND 8-OIL refrigerant oil.
( 3) - Use SUN PAG 56 refrigerant oil.
( 4) - With ambient temperature at about 80
F (27C). \
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DESCRIPTION
Slight variations exist among manual A/C-heater systems used.
On Montero, a Nippondenso 10-cylinder compressor is used. Cycling of
compressor clutch is controlled by an automatic A/C Control Unit
(ACCU).
Compressors will only operate within normal temperatures and
pressures set for each model. An electric condenser fan operates
whenever A/C system is operating. System components may vary depending
upon model. Systems may include an ACCU, fan switch, evaporator,
temperature sensor, dual-pressure switch, engine coolant temperature
switch, compressor, condenser, receiver-drier and various pipes and
hoses.
OPERATION
A/C CONTROL UNIT (ACCU)
ACCU controls cycling of compressor clutch based on
information received from air thermosensor and air inlet sensor, dual-
pressure switch, A/C switch and A/C engine coolant temperature switch.
ACCU is attached to top of evaporator housing.
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ADJUSTMENTS
NOTE: For adjustment procedures, see HEATER SYSTEM article.
TROUBLE SHOOTING
NO COOLING
1) Ensure compressor clutch is operating. If compressor
clutch is operating, go to next step. If compressor clutch is not
operating, check fuses and A/C switch. Check dual-pressure switch.
Check air inlet sensor and air thermosensor. Check A/C compressor
relay. Check A/C compressor clutch coil. Check A/C control unit.
2) Ensure system is properly charged with correct amount of
refrigerant. Evacuate and charge system as necessary. Ensure receiver-
drier is not clogged. Check compressor belt for proper tension. Check
for clogged expansion valve. Check compressor operation. Repair or
replace components as necessary.
INSUFFICIENT AIRFLOW
Check for air leakage at air duct joint. Check for frost on
evaporator. Ensure blower motor is operating properly. Check for
obstructed air intake.
INSUFFICIENT COOLING
Ensure system is properly charged with correct amount of
refrigerant and free of air and moisture. Evacuate and charge system
as necessary. Ensure receiver-drier is not clogged. Ensure sufficient
airflow through condenser exists. Check compressor belt for proper
tension. Check compressor operation. Repair or replace compressor as
necessary. Check for clogged expansion valve. Replace expansion valve
as necessary. Check A/C compressor clutch coil.
INTERMITTENT COOL AIR
Check for air or moisture in system. Evacuate and charge
system as necessary. Check for expansion valve malfunction. Replace
expansion valve if necessary. Check compressor belt for proper
tension.
TESTING
* PLEASE READ THIS FIRST *
WARNING: To avoid injury from accidental air bag deployment, read and
carefully follow all SERVICE PRECAUTIONS and DISABLING &
ACTIVATING AIR BAG SYSTEM procedures in AIR BAG RESTRAINT
SYSTEM article.
NOTE: For testing procedures not covered in this article, see
HEATER SYSTEM article.
A/C SYSTEM PERFORMANCE
1) Park vehicle out of direct sunlight. Install A/C gauge
set. Start engine and allow it to idle at 1000 RPM. Turn A/C on. Set
A/C controls to recirculated air, panel (vent) mode and full cold
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AIR BAG RESTRAINT SYSTEM
1998 Mitsubishi Montero
1998 AIR BAG RESTRAINT SYSTEMS
Mitsubishi
Montero
DESCRIPTION & OPERATION
WARNING: To avoid injury from accidental air bag deployment, read and
carefully follow all WARNINGS and SERVICE PRECAUTIONS.
Supplemental Restraint System (SRS) consists of an SRS
warning light, driver-side and passenger-side air bag module,
clockspring, right and left front impact sensors, and SRS Air Bag
Control Unit (ECU). The SRS-ECU contains an analog and a safing impact\
sensor. See Fig. 1.
Air bags are designed to deploy in a frontal or near frontal
impact of moderate to severe force. For air bags to deploy, ignition
must be on and safing impact sensor and at least one front impact
sensor must activate simultaneously.
Fig. 1: Locating SRS Components
Courtesy of Mitsubishi Motor Sales of America.
SRS WARNING LIGHT
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When ignition switch is turned to ON or START position, SRS
warning light on instrument panel should come on for about 7 seconds
and then go off. This indicates SRS-ECU has determined SRS is
functioning properly. If SRS warning light flashes, stays on all the
time, or does not come on, a fault exists in SRS. See
DIAGNOSIS & TESTING.
FRONT IMPACT SENSORS
Sensors are inertia switches that verify direction and
severity of impact. If impact is great enough, switch contacts close,
completing an electrical circuit. Front impact sensors are located
under front fenders. See Fig. 1.
AIR BAG MODULE(S)
An inflator assembly in the air bag module produces nitrogen
gas to fill air bag. See Fig. 1. When a small amount of current from
SRS-ECU is applied, ignitor starts a thermal reaction, which spreads
to a pellet-filled canister that produces nitrogen gas. Gas pressure
builds and discharges from inflator through a diffuser and screen
assembly, forcing trim cover to burst along its seams until air bag is
fully inflated. When air bag is fully inflated, gas escapes through
vents on sides of air bag.
SRS AIR BAG CONTROL UNIT (ECU)
SRS-ECU (with integral safing and analog impact sensor) is
located behind front floor console assembly. See Fig. 1. If a system
fault occurs, SRS-ECU memory stores a diagnostic trouble code (DTC).
DATA LINK CONNECTOR (DLC)
DLC is located under left side of dash. See Fig. 1. DLC is
used to access SRS self-diagnostics through Mitsubishi Multi-Use
Tester II (MUT-II) (MB991502).
CLOCKSPRING
Clockspring connects driver-side air bag module to steering
column wiring, forming SRS circuit. See Fig. 1. Clockspring is a flat,
ribbon-like cable that winds and unwinds when steering wheel is
turned. Because of clockspring's constant movement, it is the most
fragile part in the system.
SYSTEM OPERATION CHECK
WARNING: After servicing, always turn ignition on from passenger-side
of vehicle in case of accidental air bag deployment.
Turn ignition switch to ON position. SRS warning light on
instrument panel should come on for about 7 seconds and then turn off.
This indicates SRS is functioning properly. If SRS warning light does
not come on, stays on, or comes on while driving, SRS is
malfunctioning and needs repair. See DIAGNOSIS & TESTING.
SERVICE PRECAUTIONS
Observe the following precautions when working with SRS:
* Disable SRS before servicing any SRS or steering column
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component. Failure to do this may result in accidental air
bag deployment and possible personal injury. Refer to
DISABLING & ACTIVATING AIR BAG SYSTEM .
* For about 60 seconds after air bag system is disabled, it
retains enough voltage to deploy air bags. After disabling
system, wait at least 60 seconds before servicing.
* After servicing, always turn ignition on from passenger-side
of vehicle in case of accidental air bag deployment.
* After servicing, check SRS warning light to verify system
operation. See SYSTEM OPERATION CHECK.
* Always wear safety glasses when servicing or handling an
air bag.
* The SRS-ECU must be stored in its original special container
until used for service. It must be stored in a clean, dry
place, away from sources of extreme heat, sparks and high
electrical energy.
* DO NOT expose air bag module and clockspring to temperatures
greater than 200
F (93 C).
* When placing a live air bag module on a bench or other
surface, always face air bag module and trim cover up, away
from surface. This will reduce motion of module if air bag
accidentally deploys.
* After air bag deploys, air bag surface may contain deposits
of sodium hydroxide, which irritates skin. Always wear
safety glasses, rubber gloves and long-sleeved shirt during
clean-up. Wash hands using mild soap and water. Follow
correct clean-up and disposal procedures. Refer to
DISPOSAL PROCEDURES .
* Because of critical system operating requirements, DO NOT
service any SRS components. Repairs are only made by
replacing defective part(s).
* DO NOT allow any electrical source near inflator on the back
of air bag module.
* When carrying a live (undeployed) air bag module, trim cover
must be pointed away from body to minimize injury in case of
accidental air bag deployment.
* DO NOT probe wire harness connector terminals. Instead, use
SRS Check Harness (MB991530).
* DO NOT probe a wire through insulator, as this will damage
it and eventually cause failure due to corrosion.
* When performing electrical tests, prevent accidental
shorting of terminals. Such shorts can damage fuses or
components and may cause a second fault code to set, making
diagnosis of original problem more difficult.
* Never use an analog volt/ohm meter or test light in place of
a Digital Volt/Ohm Meter (DVOM). Use only a DVOM with a
maximum test current of 2 mA (milliamps) at minimum range of
resistance measurement. Also see SPECIAL TOOLS.
* If SRS is not fully functional for any reason, DO NOT drive
vehicle until system is repaired and is fully functional. DO
NOT remove bulbs, modules, sensors or other components, or
in any way disable system from operating normally. If SRS is
not functional, park vehicle until repairs are made.
SPECIAL TOOLS
To avoid air bag deployment when working on SRS, DO NOT use
electrical test equipment such as test lights, battery or A/C-powered
volt/ohmmeter, or any type of electrical equipment other than those
specified by manufacturer. See SRS RECOMMENDED TOOLS table.
SRS RECOMMENDED TOOLS TABLE
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clockspring, the steering wheel may not turn completely, or
flat cable inside clockspring may be severed, disabling SRS
system and possibly causing serious injury to driver.
Installation
1) Ensure front wheels are in straight-ahead position. Align
mating marks on clockspring. See CLOCKSPRING CENTERING under
ADJUSTMENTS. Install clockspring. To install remaining components,
reverse removal procedure. Before installing air bag module, ensure
horn switch wiring is positioned so that it will not be pinched.
2) Tighten fasteners to spec. See TORQUE SPECIFICATIONS.
Activate SRS. See DISABLING & ACTIVATING AIR BAG SYSTEM . Check AIR BAG
warning light for proper system function. SYSTEM OPERATION CHECK.
PASSENGER-SIDE AIR BAG MODULE
Removal & Installation
1) Before proceeding, see SERVICE PRECAUTIONS. Deactivate
SRS. See DISABLING & ACTIVATING AIR BAG SYSTEM .
2) Remove right-side foot shower duct and two stoppers on
either side. Remove and lower glove box. Disconnect air bag module
connector. Remove retaining bolts and passenger-side air bag module.
See Fig. 5 .
3) To install, reverse removal procedure. Tighten bolts to
specification. See TORQUE SPECIFICATIONS . Activate SRS. See procedures
under DISABLING & ACTIVATING AIR BAG SYSTEM . Check AIR BAG warning
light for proper system function. SYSTEM OPERATION CHECK.
Fig. 5: Removing Passenger-Side Air Bag Module
Courtesy of Mitsubishi Motor Sales of America.
SRS AIR BAG CONTROL UNIT (ECU)
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CAUTION: SRS-ECU connector is a double-locking mechanism. DO NOT use
excessive force when disconnecting connector.
Removal & Installation
1) Before proceeding, see SERVICE PRECAUTIONS. Deactivate
SRS. See DISABLING & ACTIVATING AIR BAG SYSTEM .
2) Remove rear and front floor console assembly. Remove
switch panel and suspension control switch. Disconnect rear console
harness connector. Remove side panel A and rear console assembly.
3) Remove shift lever. Disconnect front console harness
connector and remove front console assembly. Disconnect SRS-ECU
connector. Remove mounting bolts, bracket and SRS-ECU. See Fig. 6.
4) To install, reverse removal procedure. Tighten bolts to
specification. See TORQUE SPECIFICATIONS . Activate SRS. See procedures
under DISABLING & ACTIVATING AIR BAG SYSTEM . Check AIR BAG warning
light for proper system function. SYSTEM OPERATION CHECK.
Fig. 6: Removing SRS Air Bag Control Unit (ECU)
Courtesy of Mitsubishi Motor Sales of America.
FRONT IMPACT SENSORS
Removal & Installation
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1) Before proceeding, see SERVICE PRECAUTIONS. Deactivate
SRS. See DISABLING & ACTIVATING AIR BAG SYSTEM .
2) Remove components for access to front impact sensors as
necessary. See Fig. 7. Remove front impact sensor mounting bolts.
Slide Green section of connector to release lock. Push down on pawl.
Disconnect electrical connector. Remove front impact sensor.
3) To install, reverse removal procedure. Position sensor
with arrow facing toward front of vehicle. Tighten bolts to
specification. See TORQUE SPECIFICATIONS . Activate SRS. See procedures
under DISABLING & ACTIVATING AIR BAG SYSTEM . Check AIR BAG warning
light for proper system function. SYSTEM OPERATION CHECK.
Fig. 7: Locating Front Impact Sensors
Courtesy of Mitsubishi Motor Sales of America.
ADJUSTMENTS
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INCH Lbs. (N.m)
Air Bag Module Bolt/Nut
Driver-Side ........................................ ( 1)
Passenger-Side ..................................... ( 1)
Clockspring Screw .................................... ( 1)
SRS-ECU (Air Bag Control Unit) Bolt ............. 43 (4.9)
( 1) - Information is not available from manufacturer.
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DIAGNOSIS & TESTING
INITIAL SRS DIAGNOSTIC PROCEDURE
WARNING: Follow air bag service precautions to prevent accidental air
bag deployment and personal injury. See SERVICE PRECAUTIONS.
NOTE: Ensure battery is fully charged. If battery voltage is too
low, SRS warning light will come on. When battery voltage is
restored to normal, light will go out. Codes remain stored
for no more than about 7 days. Codes can be stored no more
than 250 times. After servicing, reconnect negative battery
cable. Erase codes using Multi-Use Tester II (MUT-II,
MB991502). Check SRS warning light to verify system
operation. See SYSTEM OPERATION CHECK.
CAUTION: Ensure ignition is off before connecting or disconnecting
scan tool at DLC.
1) Before proceeding, follow service precautions. See
SERVICE PRECAUTIONS . Turn ignition on. If SRS warning light comes on
for about 7 seconds and turns off, SRS is functioning properly at this
time.
2) If SRS warning light does not come on, or comes on and
stays on, turn ignition switch to LOCK position. Connect scan tool to
Data Link Connector (DLC). See Fig. 9. Turn ignition on. Use scan tool
to retrieve code(s).
Fig. 9: Connecting Scan Tool To Data Link Connector (DLC)
Courtesy of Mitsubishi Motor Sales of America.
TROUBLE SYMPTOMS TABLE
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Symptom Inspection Procedure
Communication With All Systems Not Possible ............ 1
Communication With SRS Only Not Possible ............... 2
Ignition Switch On (Engine Stopped)
SRS Warning Light Does Not Come On ............... DTC 43
SRS Warning Light Stays On After 7 Seconds ...... DTC 43
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INSPECTION PROCEDURE 1
The cause is probably in power supply system (including
ground circuit of diagnostic line). Check connectors and harness, and
repair if necessary.
INSPECTION PROCEDURE 2
NOTE: Refer to WIRING DIAGRAMS for connector identification.
1) Before proceeding, see SERVICE PRECAUTIONS. Deactivate
SRS. See DISABLING & ACTIVATING AIR BAG SYSTEM .
2) Measure SRS Check Harness (MB991613) connector No. 5.
Disconnect SRS-ECU connector C-122 and connect SRS check harness
connector No. 3 to C-122. Check continuity between terminal No. 20, 21
and ground. If there is no continuity, go to next step. If there is
continuity, go to step 4).
3) Check connector C-122, and repair if necessary. If
connector is okay, check for trouble symptoms. If fault exists, check
harness between SRS-ECU and ground, and repair if necessary.
4) Measure SRS check harness connector No. 5. Disconnect SRS-
ECU connector C-122 and connect SRS harness check connector No. 3 to
C-122. Connect negative battery cable. Measure voltage between
terminal No. 13 and 14, and body ground. If voltage at terminals is 9
volts or more, check harness wire between SRS-ECU and Data Link
Connector (DLC), and repair if necessary. If harness wire is okay,
replace SRS-ECU. See SRS AIR BAG CONTROL UNIT (ECU) under REMOVAL &
INSTALLATION. If voltage is not as specified, check connector C-80, C-
93, C-101, and C-132, and repair if necessary. If connectors are okay,
check for trouble symptoms. If fault exists, check harness between
SRS-ECU and IG1 A or B (ignition switch), and repair if necessary.
Fig. 10: Identifying SRS Check Harness (MB991613) Connectors
Courtesy of Mitsubishi Motor Sales of America.
DTC 11, 12 & 13: FRONT IMPACT SENSOR SYSTEM