wiring MITSUBISHI MONTERO 1991 Service Manual
[x] Cancel search | Manufacturer: MITSUBISHI, Model Year: 1991, Model line: MONTERO, Model: MITSUBISHI MONTERO 1991Pages: 1333, PDF Size: 24.61 MB
Page 1196 of 1333
Engine overheated See ENGINE COOLING
SYSTEM article
Engine oil too heavy Check that proper
viscosity oil
is used
Poor battery-to-starter Check that all
connections between
battery and starter are
clean and tight
Current draw too low or See Bench Tests in
too high STARTER article
Bent armature, loose pole See STARTER article
shoes screws or worn
bearings
Burned solenoid contacts Replace solenoid
Faulty starter Replace starter
\
\
\
\
\
\
\
Starter Engages Engine timing too far See Ignition Timing in
Engine Only advanced TUNE-UP article
Momentarily
Overrunning clutch not Replace overrunning
engaging properly clutch. See STARTER
article
Broken starter clutch See STARTER article
Broken teeth on engine Replace flywheel and
flywheel check starter pinion
gear for damage
Weak drive assembly See STARTER article
thrust spring
Weak hold-in coil See Bench Tests in
STARTER article
\
\
\
\
\
\
\
Starter Drive Defective point assembly See Testing in STARTER
Will Not Engage article
Poor point assembly ground See Testing in STARTER
article
Defective pull-in coil Replace starter
solenoid
\
\
\
\
\
\
\
Starter Relay Dead battery Charge or replace
Does Not Close battery as necessary
Faulty wiring Check all wiring and
connections leading to
relay
Neutral safety switch Replace neutral safety
faulty switch
Starter relay faulty Replace starter relay
Page 1197 of 1333
![MITSUBISHI MONTERO 1991 Service Manual \
\
\
\
\
\
\
Starter Drive Starter motor loose on](/img/19/57332/w960_57332-1196.png "MITSUBISHI MONTERO 1991 Service Manual \
\
\
\
\
\
\
Starter Drive Starter motor loose on")
\
\
\
\
\
\
\
Starter Drive Starter motor loose on Tighten starter
Will Not mountings attach bolts
Disengage
Worn drive end bushing See STARTER article
Damaged engine flywheel Replace flywheel and
teeth starter pinion gear for
damage
Drive yolk return spring Replace return spring
broken or missing
Faulty ignition switch Replace ignition switch
Insufficient clearance Replace starter
between winding leads to solenoid
solenoid terminal and main
contact in solenoid
Starter clutch not Replace starter clutch
disengaging
Ignition starter switch Replace ignition switch
contacts sticking
\
\
\
\
\
\
\
Starter Relay Faulty solenoid switch, Check all wiring
Operates but switch connections or between relay and
Solenoid Does Not solenoid or replace
relay or solenoid as
necessary
Broken lead or loose Repair wire or wire
soldered connections connections as
necessary
\
\
\
\
\
\
\
Solenoid Plunger Weak battery Charge or replace
Vibrates When battery as necessary
Switch is Engaged
Solenoid contacts Clean contacts or
corroded replace solenoid
Faulty wiring Check all wiring
leading to solenoid
Broken connections inside Repair connections or
switch cover replace solenoid
Open hold-in wire Replace solenoid
\
\
\
\
\
\
\
Low Current Draw Worn brushes or weak Replace brushes or
brush springs as
necessary
\
\
\
\
\
\
\
High Pitched Whine Distance too great Align starter or check
During Cranking between starter that correct starter
Before Engine pinion and flywheel and flywheel are being
Fires but Engine used
Fires and Cranks
Normally
\
\
\
\
\
\
\
High Pitched Distance too small between
Whine After Engine starter pinion and flywheel
Page 1199 of 1333
problem symptoms. For model-specific Trouble Shooting,
refer to DIAGNOSTIC, or TESTING articles available in the
section(s) you are accessing.
BASIC HEATER SYSTEM TROUBLE SHOOTING CHART
\
\
\
\
\
\
\
CONDITION POSSIBLE CAUSE \
\
\
\
\
\
\
Insufficient, Erratic,
or No Heat
Low Coolant Level
Incorrect thermostat.
Restricted coolant flow through
heater core.
Heater hoses plugged.
Misadjusted control cable.
Sticking heater control valve.
Vacuum hose leaking.
Vacuum hose blocked.
Vacuum motors inoperative.
Blocked air inlet.
Inoperative heater blower motor.
Oil residue on heater core fins.
Dirt on heater core fins. \
\
\
\
\
\
\
Too Much Heat
Improperly adjusted cables.
Sticking heater control valve.
No vacuum to heater control valve.
Temperature door stuck open. \
\
\
\
\
\
\
Air Flow Changes During
Acceleration
Vacuum system leak.
Bad check valve or reservoir. \
\
\
\
\
\
\
Air From Defroster At All
Times
Vacuum system leak.
Improperly adjusted control cables.
Inoperative vacuum motor. \
\
\
\
\
\
\
Blower Does Not Operate
Correctly
Blown fuse.
Blower motor windings open.
Resistors burned out.
Motor ground connection loose.
Wiring harness connections loose.
Blower motor switch inoperative.
Blower relay inoperative.
Fan binding or foreign object
in housing.
Fan blades broken or bent. \
\
\
\
\
\
\
BRAKES
BRAKE SYSTEM TROUBLE SHOOTING
NOTE: This is GENERAL information. This article is not intended
to be specific to any unique situation or individual vehicle
configuration. The purpose of this Trouble Shooting
information is to provide a list of common causes to
problem symptoms. For model-specific Trouble Shooting,
refer to SUBJECT, DIAGNOSTIC, or TESTING articles available
in the section(s) you are accessing.
Page 1214 of 1333
![MITSUBISHI MONTERO 1991 Service Manual Incorrect injector pump Check pressure, see
housing pressure FUEL SYSTEMS
\
\
\](/img/19/57332/w960_57332-1213.png "MITSUBISHI MONTERO 1991 Service Manual Incorrect injector pump Check pressure, see
housing pressure FUEL SYSTEMS
\
\
\")
Incorrect injector pump Check pressure, see
housing pressure FUEL SYSTEMS
\
\
\
\
\
\
\
Engine Cooling system leaks Check cooling system
Overheating and repair leaks
Belt slipping or damaged Check tension and/or
replace belt
Thermostat stuck closed Remove and replace
thermostat, see
ENGINE COOLING
Head gasket leaking Replace head gasket
\
\
\
\
\
\
\
Oil Light on at Low oil pump pressure Check oil pump
Idle operation, see ENGINES
Oil cooler or line Remove restriction
restricted and/or replace cooler
\
\
\
\
\
\
\
Engine Won't Injector pump fuel solenoid Remove and check
Shut Off does not return fuel valve solenoid and replace
to OFF position if needed
\
\
\
\
\
\
\
VACUUM PUMP DIAGNOSIS
Excessive Noise Loose pump-to-drive Tighten screws
assembly screws
Loose tube on pump assembly Tighten tube
Valves not functioning Replace valves
properly
Oil Leakage Loose end plug Tighten end plug
Bad seal crimp Remove and re-crimp
seal
\
\
\
\
\
\
\
FUEL INJECTION TROUBLE SHOOTING
NOTE: This is GENERAL information. This article is not intended
to be specific to any unique situation or individual vehicle
configuration. The purpose of this Trouble Shooting
information is to provide a list of common causes to
problem symptoms. For model-specific Trouble Shooting,
refer to SUBJECT, DIAGNOSTIC, or TESTING articles available
in the section(s) you are accessing.
BASIC FUEL INJECTION TROUBLE SHOOTING CHART
\
\
\
\
\
\
\
CONDITION POSSIBLE CAUSE CORRECTION \
\
\
\
\
\
\
Engine Won't Cold start valve inoperative Test valve and
Start (Cranks circuit
Normally)
Poor connection;vacuum or Check vacuum and
wiring electrical
connections
Contaminated fuel Test fuel for water
or alcohol
Defective fuel pump relay Test relay and
or circuit wiring
Battery too low Charge and test
battery
Page 1215 of 1333
Low fuel pressure Test pressure regul-
ator and fuel pump,
check for restricted
lines and filters
No distributor reference Repair ignition
pulses system as necessary
Open coolant temperature Test sensor and
sensor circuit wiring
Shorted W.O.T. switch in Disconnect W.O.T.
T.P.S. switch, engine
should start
Defective ECM Replace ECM
Fuel tank residual pressure Test for fuel
valve leaks pressure drop after
shut down
\
\
\
\
\
\
\
Hard Starting Disconnected hot air tube Reconnect tube and
to air cleaner test control valve
Defective Idle Air Control Test valve operation
(IAC) valve and circuit
Shorted, open or misadjusted Test and adjust or
T.P.S. replace T.P.S.
EGR valve open Test EGR valve and
control circuit
Poor Oxygen sensor signal Test for shorted or
circuit
Incorrect mixture from PCV Test PCV for flow,
system check sealing of oil
filter cap
\
\
\
\
\
\
\
Poor High Speed Low fuel pump volume Faulty pump or
Operation restricted fuel
lines or filters
Poor MAP sensor signal Test MAP sensor,
vacuum hose and
wiring
Poor Oxygen sensor signal Test for shorted or
open sensor or
circuit
Open coolant temperature Test sensor and
sensor circuit wiring
Faulty ignition operation Check wires for
cracks or poor con-
nections, test
secondary voltage
with oscilloscope
Contaminated fuel Test fuel for water
Page 1221 of 1333
Does Not Close battery as necessary
Faulty wiring Check all wiring and
connections leading to
relay
Neutral safety switch Replace neutral safety
faulty switch
Starter relay faulty Replace starter relay
\
\
\
\
\
\
\
Starter Drive Starter motor loose on Tighten starter
Will Not mountings attach bolts
Disengage
Worn drive end bushing See STARTER article
Damaged engine flywheel Replace flywheel and
teeth starter pinion gear for
damage
Drive yolk return spring Replace return spring
broken or missing
Faulty ignition switch Replace ignition switch
Insufficient clearance Replace starter
between winding leads to solenoid
solenoid terminal and main
contact in solenoid
Starter clutch not Replace starter clutch
disengaging
Ignition starter switch Replace ignition switch
contacts sticking
\
\
\
\
\
\
\
Starter Relay Faulty solenoid switch, Check all wiring
Operates but switch connections or between relay and
Solenoid Does Not solenoid or replace
relay or solenoid as
necessary
Broken lead or loose Repair wire or wire
soldered connections connections as
necessary
\
\
\
\
\
\
\
Solenoid Plunger Weak battery Charge or replace
Vibrates When battery as necessary
Switch is Engaged
Solenoid contacts Clean contacts or
corroded replace solenoid
Faulty wiring Check all wiring
leading to solenoid
Broken connections inside Repair connections or
switch cover replace solenoid
Open hold-in wire Replace solenoid
\
\
\
\
\
\
\
Low Current Draw Worn brushes or weak Replace brushes or
brush springs as
necessary
Page 1222 of 1333
![MITSUBISHI MONTERO 1991 Service Manual \
\
\
\
\
\
\
High Pitched Whine Distance too great](/img/19/57332/w960_57332-1221.png "MITSUBISHI MONTERO 1991 Service Manual \
\
\
\
\
\
\
High Pitched Whine Distance too great")
\
\
\
\
\
\
\
High Pitched Whine Distance too great Align starter or check
During Cranking between starter that correct starter
Before Engine pinion and flywheel and flywheel are being
Fires but Engine used
Fires and Cranks
Normally
\
\
\
\
\
\
\
High Pitched Distance too small between
Whine After Engine starter pinion and flywheel
Fires With Key Flywheel runout contributes
released. Engine to the intermittent nature
Fires and Cranks
Normally
\
\
\
\
\
\
\
TUNE-UP TROUBLE SHOOTING - GAS ENGINE VEHICLES
NOTE: This is GENERAL information. This article is not intended
to be specific to any unique situation or individual vehicle
configuration. The purpose of this Trouble Shooting
information is to provide a list of common causes to
problem symptoms. For model-specific Trouble Shooting,
refer to SUBJECT, DIAGNOSTIC, or TESTING articles available
in the section(s) you are accessing.
BASIC SPARK PLUG TROUBLE SHOOTING CHARTS
\
\
\
\
\
\
\
CONDITION POSSIBLE CAUSE CORRECTION \
\
\
\
\
\
\
Normal Spark Light Tan or Gray deposits No Action
Plug Condition
Electrode not burned or No Action
fouled
Gap tolerance not changed No Action
\
\
\
\
\
\
\
Cold Fouling or Overrich air/fuel mixture Adjust air/fuel
Carbon Deposits mixture, see ENGINE
PERFORMANCE section
Faulty choke Replace choke
assembly, see ENGINE
PERFORMANCE section
Clogged air filter Clean and/or replace
air filter
Incorrect idle speed or Reset idle speed and/
dirty carburetor or clean carburetor
Faulty ignition wires Replace ignition
wiring
Prolonged operation Shut engine off
at idle during long idle
Sticking valves or worn Check valve train
valve guide seals
\
\
\
\
\
\
\
Wet Fouling Worn rings and pistons Install new rings and
or Oil Deposits pistons
Page 1223 of 1333
Excessive cylinder wear Rebore or replace
block
Excessive valve guide Worn or loose bearing
clearance
\
\
\
\
\
\
\
Gap Bridged Deposits in combustion Clean combustion
chamber becoming fused chamber of deposits
to electrode
\
\
\
\
\
\
\
Blistered Engine overheating Check cooling system
Electrode
Wrong type of fuel Replace with correct
fuel
Loose spark plugs Retighten spark plugs
Over-advanced ignition Reset ignition timing
timing see ENGINE PERFORMANCE
\
\
\
\
\
\
\
Pre-Ignition or Incorrect type of fuel Replace with correct
Melted Electrodes fuel
Incorrect ignition timing Reset ignition timing
see ENGINE PERFORMANCE
Burned valves Replace valves
Engine Overheating Check cooling system
Wrong type of spark plug, Replace with correct
too hot spark plug, see
ENGINE PERFORMANCE
\
\
\
\
\
\
\
Chipped Severe detonation Check for over-
Insulators advanced timing or
combustion
Improper gapping Re-gap spark plugs
procedure
\
\
\
\
\
\
\
Rust Colored Additives in unleaded Try different fuel
Deposits fuel brand
\
\
\
\
\
\
\
Water In Combus- Blown head gasket or Repair or replace
tion Chamber cracked head head or head gasket
\
\
\
\
\
\
\
NOTE: Before diagnosing an electronic ignition system, ensure that
all wiring is connected properly between distributor, wiring
connector and spark plugs. Ignition problem will show up
either as: Engine Will Not Start or Engine Runs Rough.
BASIC ELECTRONIC IGNITION TROUBLE SHOOTING CHARTS
\
\
\
\
\
\
\
CONDITION POSSIBLE CAUSE CORRECTION \
\
\
\
\
\
\
Engine Won't Open circuit between Repair circuit
Start distributor and bulkhead
connector
Open circuit between Repair circuit
bulkhead connector and
Page 1224 of 1333
![MITSUBISHI MONTERO 1991 Service Manual ignition switch
Open circuit between Repair circuit
ignition switch and
starter solenoid
\](/img/19/57332/w960_57332-1223.png "MITSUBISHI MONTERO 1991 Service Manual ignition switch
Open circuit between Repair circuit
ignition switch and
starter solenoid
\")
ignition switch
Open circuit between Repair circuit
ignition switch and
starter solenoid
\
\
\
\
\
\
\
Engine Runs Fuel lines leaking or Tighten fitting,
Rough clogged remove restriction
Initial timing incorrect Reset ignition timing
see ENGINE PERFORMANCE
Centrifugal advance Repair distributor
malfunction advance
Defective spark plugs or Replace plugs or plug
wiring wiring
\
\
\
\
\
\
\
Component Failure Spark arc-over on cap, Replace cap, rotor or
rotor or coil or coil
Defective pick-up coil Replace pick-up coil
Defective ignition coil Replace ignition coil
Defective vacuum unit Replace vacuum unit
Defective control module Replace control module
\
\
\
\
\
\
\
BASIC ELECTRONIC IGNITION TROUBLE SHOOTING
CHARTS - USING OSCILLOSCOPE PATTERNS
\
\
\
\
\
\
\
CONDITION POSSIBLE CAUSE CORRECTION \
\
\
\
\
\
\
Firing Voltage Retarded ignition timing Reset ignition
Lines are the Same, timing, see ENGINE
but Abnormally High PERFORMANCE section
Fuel mixture too lean Readjust carburetor,
see ENGINE PERFORMANCE
High resistance in coil Replace coil wire
wire
Corrosion in coil tower Clean and/or replace
terminal coil
Corrosion in distributor Clean and/or replace
coil terminal distributor cap
\
\
\
\
\
\
\
Firing Voltage Fuel mixture too rich Readjust carburetor,
Lines are the Same see ENGINE PERFORMANCE
but Abnormally Low
Breaks in coil wire causing Replace coil wire
arcing
Cracked coil tower causing Replace coil
arcing
Low coil output Replace coil
Low engine compression Determine cause and
Page 1229 of 1333
Vacuum leak Repair vacuum leak
Improper float bowl fuel Reset float
level adjustment, see FUEL
Clogged air bleed or idle Clean carburetor
passages passages, see FUEL
Clogged or worn air cleaner Replace air filter
filter
Faulty choke vacuum Replace diaphragm,
diaphragm see ENGINE PERFORMANCE
Exhaust manifold heat valve Replace heat valve
inoperative
Improper distributor spark Check distributor
advance operation
Leaking valves or valve Check and repair
components valvetrain
Improper carburetor Remove and remount
mounting carburetor
Excessive play in Replace distributor
distributor shaft
Loose or corroded wiring Repair or replace as
connections required
\
\
\
\
\
\
\
Engine Surges Improper PCV valve airflow Replace PCV valve
Vacuum leaks Repair vacuum leaks
Clogged air bleeds Remove restriction
EGR valve malfunction Replace EGR valve
Restricted air cleaner Replace air filter
filter
Cracked or broken vacuum Replace vacuum hoses
hoses
Cracked or broken ignition Replace ignition
wires wires
Vacuum advance malfunction Check unit and
replace as necessary
Defective or fouled spark Replace spark plugs
plugs
\
\
\
\
\
\
\
Ping or Spark Incorrect ignition timing Reset ignition timing
Knock see ENGINE PERFORMANCE
Distributor centrifugal or Check operation and
vacuum advance malfunction replace as necessary
Carburetor setting too lean Readjust mixture