check engine light JEEP CHEROKEE 1988 Service Owner's Guide
[x] Cancel search | Manufacturer: JEEP, Model Year: 1988, Model line: CHEROKEE, Model: JEEP CHEROKEE 1988Pages: 1378, PDF Size: 19.9 MB
Page 1007 of 1378
SER VIC E IN DIC ATO R & W AR NIN G L IG HTS
1988 J e ep C hero ke e
1984-92 MAINTENANCE
AMC/Jeep/Eagle Service Indicator & Warning Lights
Jeep; Cherokee, Wagoneer
SERVICE INDICATOR & WARNING LIGHTS
BRAKE WARNING LIGHT
If the light stays on when the parking brake is off, it
indicates a possible brake system fluid leak or low pressure level.
LOCK INDICATOR LIGHT (1984-87)
Indicates that Selec-Trac transfer case is in part time 4WD
(high or low range).
FULL TIME 4WD INDICATOR LIGHT
Indicates that Selec-Trac transfer case is in full-time 4WD
(4x4 FULL TIME).
PART TIME 4WD INDICATOR LIGHT
Indicates that Selec-Trac transfer case is in part time 4WD
(4x4 PART TIME or 4 LO) or that Command-Trac transfer case is in 4WD
(4H or 4L).
WATER IN FUEL LIGHT (TURBO DIESEL)
Indicates water has collected in the fuel filter and should
be drained immediately.
DIESEL WAIT LIGHT (TURBO DIESEL)
Illuminates during glow plugs warm-up cycle.
LOW FUEL WARNING LIGHT
Glows when approximately 2 gals. (7.6L) remain in fuel tank.
EMISSION MAINTENANCE INDICATOR LIGHT
Illuminates at approximately 82,500 miles to indicate
scheduled maintenance (or recommended maintenance on California
vehicles). Light will remain on until system is serviced and light is
reset.
CHECK ENGINE LIGHT
If this light illuminates and remains on while driving, it
indicates a potential engine control problem that needs service.
CHECK ANTI-LOCK LIGHT
Illuminates to indicate a self-check is in process at vehicle
start up. If light remains on after start-up or comes on and stays on
Page 1008 of 1378
at road speeds, it may indicate that the ABS system has detected a
malfunction or has become inoperative. The system reverts to standard
non-anit-lock brakes. If both Red BRAKE light and Amber CHECK ANTI-
LOCK light are on, have vehicle serviced immediately.
Fig. 1: Instrument Panel Interior Controls
Courtesy of Chrysler Motors.
Fig. 2: Dash Gauges & Warning Lights (Gasoline Engines)
Courtesy of Chrysler Motors.
Page 1015 of 1378
reading of .2 volt or less. If reading exceeds .2 volt, clean or
repair cables and connections in circuit. Connect a voltmeter at
following locations:
* Positive lead to battery positive post and negative lead
to cable clamp.
* Positive lead to battery negative post and negative lead
to cable clamp.
3) If reading is other than zero on voltmeter, clean or
repair cables and connections in circuit. Connect a voltmeter at
following location:
* Positive lead to battery positive post and negative lead
to starter solenoid lead to the field coils.
4) If reading exceeds .3 volt, clean or repair cables and
connections in circuit.
SOLENOID TEST
1) Connect a heavy jumper wire on starter relay between
battery and solenoid terminals. If engine cranks, solenoid is okay. Go
to RELAY TEST .
2) If engine does not crank, check wiring and connections
from relay to starter. Repair or replace as necessary. If engine still
fails to crank, starter is defective.
RELAY TEST
1) On automatic transmission/transaxle vehicles, put gear
selector in "NEUTRAL" or "PARK". On manual transmission/transaxle
vehicles, put gear selector in "NEUTRAL". Set parking brake and block
wheels. DO NOT remove relay connector. Using a 12-volt test light,
check for battery voltage between starter relay battery terminal and
ground.
2) Use a jumper wire on starter relay between battery and
ignition terminals. If engine cranks starter relay is good. If starter
does not crank go to next step.
3) Connect another jumper wire to starter relay between
ground terminal and ground. Repeat above test. If engine cranks,
starter relay is good. Inspect transmission linkage for improper
adjustment (automatic transmission), defective neutral safety switch
(automatic transmission) or poor ground connection between relay
housing and mounting surface.
TESTING (ON BENCH)
STARTER SOLENOID
1) With starter removed, disconnect field coil wire from
field coil terminal on starter. Using an ohmmeter, check for
continuity between solenoid and field coil terminals.
2) Check for continuity between solenoid terminal solenoid
housing. Continuity should be present in both tests. If continuity is
present, solenoid is good. If no continuity is present, replace
solenoid. Reconnect field coil wire to field coil terminal.
ARMATURE FOR SHORT CIRCUIT
Place armature in a growler and hold a thin steel blade
parallel 3/16" above core while rotating armature slowly. If armature
Page 1215 of 1378
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TR AN SM IS SIO N S ER VIC IN G - A /T
1988 J e ep C hero ke e
1988 Automatic Transmission Servicing
JEEP
LUBRICATION
SERVICE INTERVALS
Transmission
Check fluid level and condition of fluid at each engine oil
change. Under normal, light duty operating conditions, change fluid,
replace filter and adjust bands every 2 yrs. or 25,000 miles. Under
heavy duty service, change fluid, replace filter and adjust bands
every 12 months or 12,500 miles.
Transfer Case
Check transfer case fluid every 12,000 miles and replace
fluid every 30,000 miles.
CHECKING FLUID LEVEL
Transmission
Park vehicle on a level surface and apply parking brake.
With engine idling at normal operating temperature, move transmission
selector lever through all gears, ending in "N" ("P" for AW-4
transmission). Check fluid level. Fluid level should be between
"FULL" and "ADD ONE PINT" mark on dipstick. Add fluid as needed. DO
NOT overfill.
Transfer Case
Remove fill plug. Check oil level. If level is not up to
fill plug opening, add lubricant until it is.
RECOMMENDED FLUID
Both transmissions and transfer cases use DEXRON-II ATF.
FLUID CAPACITY
NOTE: Transmission and converter capacities are approximate. Fluid
level should always be determined by reading on dipstick,
rather than amount of fluid added.
TRANSMISSION REFILL CAPACITIES
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Application Quantity
All Models
Including Converter ................................ 8.5 qts. (8.0L)\
Without Converter .................................. 4.3 qts. (4.0L)\
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TRANSFER CASE REFILL CAPACITIES \
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Application Capacity
Model 207 ............................................ 4.5 pts. (2.1L)\
Model 208 ............................................ 6.0 pts. (2.8L)\
Page 1218 of 1378
3) Loosen bolt on throttle control link. Pull on link end to
eliminate lash. Tighten adjusting bolt. Press extend button on
Exerciser Box. When ISA retracts, release button and disconnect
Exerciser Box. Connect ISA wiring and remove spring from throttle
control lever. Install and reconnect any parts removed and/or
disconnected.
999 Transmission with 6-Cylinder Engines
1) Disconnect throttle control rod spring. Use spring to
hold adjusting link in forward position, against nylon washer. Block
choke open and release fast idle cam.
2) Raise vehicle. Loosen both retaining bolts on adjusting
link clamp. DO NOT remove spring clip or nylon washer. Use a spare
spring to hold transmission throttle lever against forward stop.
3) Push adjusting link to eliminate lash and pull clamp to
rear so that bolt in rod bottoms in rear of slot in rod. Tighten
forward clamp retaining bolt.
4) Pull throttle control rod to the rear so that bolt in
rod bottoms in front of slot and tighten rear retaining bolt. Remove
spare spring. Lower vehicle and reconnect throttle control rod spring.
AW-4 Transmission with All Engines
1) With ignition off, retract cable self-adjusting mechanism
fully. Press cable button down and push cable plunger inward.
2) Rotate throttle lever to wide open throttle position.
While holding throttle lever in position, allow cable plunger to
extend. When plunger is fully extended, release throttle lever. Cable
is now adjusted.
SHIFT LINKAGE
Cable Linkage
1) Place gearshift lever in "P" position and raise vehicle.
Using a small screwdriver, unlock shift control cable by releasing
U-shaped cable adjuster clamp. Remove cable from mounting bracket.
2) Move transmission shift lever rearward until fully
seated into "P" detent. Ensure that driveshaft cannot be rotated.
Snap control cable into cable mounting bracket and replace U-shaped
cable adjuster clamp.
3) Lower vehicle and verify engine starting. Engine should
start only with shifter in "P" or "N" position.
Rod Linkage
1) Loosen shift rod trunnion jam nuts at transmission lever.
Remove shift rod-to-bellcrank lock pin. Disengage trunnion and shift
rod. Place selector lever in "P" position and lock steering column.
Move transmission shift lever to full rear Park position.
2) Adjust shift rod trunnion to obtain free pin fit in
bellcrank arm. Tighten jam nuts. On vehicles with shift lever on
column, make sure linkage lash is eliminated by pulling down on shift
rod and pushing up on outer bellcrank when tightening jam nuts.
3) Check steering column lock for ease of operation. Ensure
engine starts in "N" or "P", only. If starter engages in any drive
gear, or does not work in "N" or "P", check for proper shift linkage
adjustment or faulty neutral safety switch.
NEUTRAL SAFETY SWITCH
1) Switch combines functions of neutral safety switch and
back-up light switch. With transmission linkage properly adjusted,
switch should allow starter operation in "P" and "N" only.
2) To test switch, remove wire connector and test for
continuity between center pin of switch and case. Continuity should
Page 1222 of 1378
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TR O UBLE S H O OTIN G - B ASIC P R O CED URES
1988 J e ep C hero ke e
GENERAL TROUBLE SHOOTING
* PLEASE READ THIS FIRST *
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.
ACCESSORIES & ELECTRICAL
CHARGING 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.
BASIC CHARGING SYSTEM TROUBLE SHOOTING CHART
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CONDITION POSSIBLE CAUSE CORRECTION \
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Vehicle Will Not Dead battery Check battery cells,
Start alternator belt
tension and alternator
output
Loose or corroded battery Check all charging
connections system connections
Ignition circuit or switch Check and replace as
malfunction necessary
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Alternator Light Loose or worn alternator Check alternator drive
Stays On With drive belt tension and
Engine Running condition, See Belt
Adjustment in TUNE-UP
article in the
TUNE-UP section
Loose alternator wiring Check all charging
connections system connections
Short in alternator light See Indicator Warning
wiring Lights in STANDARD
INSTRUMENTS in the
ACCESSORIES &
EQUIPMENT section
Defective alternator stator See Bench Tests in
or diodes ALTERNATOR article
Defective regulator See Regulator Check in
Page 1227 of 1378
![JEEP CHEROKEE 1988 Service Owners Guide Open solenoid pull-in See Testing in STARTER
wire article
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Open solenoid pull-in See Testing in STARTER
wire article
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Starter Does Not Weak battery or dead Charge or replace
Operate and cell battery as necessary
Headlights Dim
Loose or corroded battery Check that battery
connections connections are clean
and tight
Internal ground in See Testing in STARTER
starter windings article
Grounded starter fields See Testing in STARTERS
Armature rubbing on pole See STARTER article
shoes
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Starter Turns Starter clutch slipping See STARTER article
but Engine
Does Not Rotate
Broken clutch housing See STARTER article
Pinion shaft rusted or See STARTER article
dry
Engine basic timing See Ignition Timing in
incorrect TUNE-UP article
Broken teeth on engine Replace flywheel and
flywheel check for starter pinion
gear damage
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Starter Will Not Faulty overrunning See STARTER article
Crank Engine clutch
Broken clutch housing See STARTER article
Broken flywheel teeth Replace flywheel and
check for starter pinion
gear damage
Armature shaft sheared See STARTER article
or reduction gear teeth
stripped
Weak battery Charge or replace
battery as necessary
Faulty solenoid See On-Vehicle Tests in
STARTER article
Poor grounds Check all ground
connections for
tight and clean
connections
Ignition switch faulty Adjust or replace
or misadjusted ignition switch as
necessary
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Starter Cranks Battery weak or Charge or replace
Engine Slowly defective battery as necessary
Page 1246 of 1378
![JEEP CHEROKEE 1988 Service Owners Guide Incorrect injector pump Check pressure, see
housing pressure FUEL SYSTEMS
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Incorrect injector pump Check pressure, see
housing pressure FUEL SYSTEMS
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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
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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
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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
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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
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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
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CONDITION POSSIBLE CAUSE CORRECTION \
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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 1251 of 1378
Ignition switch faulty Adjust or replace
or misadjusted ignition switch
Open circuit between Check and repair wires
starter switch ignition and connections as
terminal on starter relay necessary
Starter relay or starter See Testing in STARTER
defective article
Open solenoid pull-in See Testing in STARTER
wire article
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Starter Does Not Weak battery or dead Charge or replace
Operate and cell battery as necessary
Headlights Dim
Loose or corroded battery Check that battery
connections connections are clean
and tight
Internal ground in See Testing in STARTER
starter windings article
Grounded starter fields See Testing in STARTERS
Armature rubbing on pole See STARTER article
shoes
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Starter Turns Starter clutch slipping See STARTER article
but Engine
Does Not Rotate
Broken clutch housing See STARTER article
Pinion shaft rusted or See STARTER article
dry
Engine basic timing See Ignition Timing in
incorrect TUNE-UP article
Broken teeth on engine Replace flywheel and
flywheel check for starter pinion
gear damage
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Starter Will Not Faulty overrunning See STARTER article
Crank Engine clutch
Broken clutch housing See STARTER article
Broken flywheel teeth Replace flywheel and
check for starter pinion
gear damage
Armature shaft sheared See STARTER article
or reduction gear teeth
stripped
Weak battery Charge or replace
battery as necessary
Faulty solenoid See On-Vehicle Tests in
STARTER article
Poor grounds Check all ground
Page 1254 of 1378
![JEEP CHEROKEE 1988 Service Owners Guide \
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High Pitched Whine Distance too great")
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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
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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
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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
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CONDITION POSSIBLE CAUSE CORRECTION \
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Normal Spark Light Tan or Gray deposits No Action
Plug Condition
Electrode not burned or No Action
fouled
Gap tolerance not changed No Action
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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
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Wet Fouling Worn rings and pistons Install new rings and
or Oil Deposits pistons