transmission JEEP CHEROKEE 1988 Service User Guide
[x] Cancel search | Manufacturer: JEEP, Model Year: 1988, Model line: CHEROKEE, Model: JEEP CHEROKEE 1988Pages: 1378, PDF Size: 19.9 MB
Page 96 of 1378
mm Millimeters
M/T Manual Transaxle or Transmission
MA PFI Mass Air Sequential Port Fuel Injection system
MA or MAF Mass Airflow
MAF Mass Air Flow sensor
MAFS Mass Airflow Sensor
MAP Manifold Absolute Pressure sensor
MAT Manifold Air Temperature
MCU Microprocessor Control Unit
MCV Mixture Control Valve
MEM-CAL Memory Calibration Chip
MFI Multiport Fuel Injection
MIL Malfunction Indicator Light
MLP Manual Lever Position
MPFI Multi Point Fuel Injection
MPH Miles Per Hour
MPI Multi-Point (Fuel) Injection
Man. Manual
Mech. Mechanical
Mem. Memory
Mtr. Motor
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"N" ABBREVIATION TABLE
"N" ABBREVIATION TABLE \
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ABBREVIATION DEFINITION
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N.m Newton-Meter
NA Not Available
NDS Neutral Drive Switch
NGS Neutral Gear Switch
NOx Oxides of Nitrogen
NPS Neutral Pressure Switch
No. Number
Nos. Numbers
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"O" ABBREVIATION TABLE
"O" ABBREVIATION TABLE \
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ABBREVIATION DEFINITION
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O Oxygen
O.D. Outside Diameter
O/S Oversize
O2 Oxygen
OC Oxidation Catalyst
OCC Output Circuit Check
OD Overdrive
ODO Odometer
OHC Overhead Camshaft
ORG Orange
OSC Output State Check
Opt. Option or Optional
oz. Ounce
ozs. Ounces
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TCC Torque Converter Clutch
TCCS Toyota Computer Control System
TDC Top Dead Center
TDCL Total Diagnostic Communication Link
TFI Thick Film Ignition system
TGS Top Gear Switch (cancels SIL in top gear)
THERMAC Thermostatic Air Cleaner
THS Transmission Hydraulic Switch
TP/TPS Throttle Position Sensor
TPI Tuned Port Injection
TPS Throttle Position Sensor/Switch
TS Temperature Sensor
TSB Technical Service Bulletin
TTS Transmission Temperature Switch
TV Thermovalve
TWC Three-Way Catalyst
Temp. Temperature
Trans. Transaxle/Transmission
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"V" ABBREVIATION TABLE
"V" ABBREVIATION TABLE \
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ABBREVIATION DEFINITION
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V Valve
VAF Vane Air Flow sensor or circuit
VAPS Variable Assist Power Steering
VAT Vane Air Temperature
VATS Vehicle Anti-Theft System
VBATT Vehicle Battery Voltage
VCC Viscous Converter Clutch
VIN Vehicle Identification Number
VIO Violet
VLR Volt Loop Reserve
VM Vacuum Modulator
VM Vane Meter
VOM Volt-Ohmmeter (Analog)
VPWR Vehicle Power supply voltage (10-14 volts)
VREF Voltage Reference (ECA supplied reference voltage
VRV Vacuum Regulator Valve
VSC Vehicle Speed Control sensor or signal
VSS Vehicle Speed Sensor or signal
VSV Vacuum Switching Valve
Vac. Vacuum
Volt. Voltage
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"W" ABBREVIATION TABLE
"W" ABBREVIATION TABLE \
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ABBREVIATION DEFINITION
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W/ With
W/O Without
WAC WOT A/C Cut-off switch or circuit
WAC Wide Open Throttle A/C Switch
WHT White
WOT Wide Open Throttle
YEL Yellow
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of the scale, a symbol for defroster indicates defrost position. In
"BI-LEVEL" position, a mixture of floor heat and defroster air is
obtained.
The lower temperature control lever operates blend-air door
in heater core housing. At full right position, all air is directed
through heater core, providing maximum heat flow. At full left
position, all air is directed around heater core providing fresh air.
Control can be set in any intermediate position to provide a blend of
heated and unheated air. Heater must be in heat or defrost mode before
any air can enter vehicle.
TROUBLE SHOOTING
See JEEP TROUBLE SHOOTING at the end of this article.
REMOVAL & INSTALLATION
CONDENSER
Removal (Cherokee, Comanche & Wagoneer) NOTE: On these
models, condenser and receiver-drier are replaced
as a unit.
1) Drain radiator. Disconnect fan shroud and radiator hoses.
Disconnect automatic transmission cooler lines (if equipped).
Discharge A/C system using approved refrigerant recovery/recycling
equipment.
2) Disconnect A/C hoses from condenser. Unplug low pressure
switch. Remove radiator and condenser as an assembly. Detach condenser
retaining bolts. Separate condenser from radiator. Remove receiver-
drier from condenser.
NOTE: Plug receiver-drier openings whenever unit is removed from
condenser. Add 1 oz. of refrigerant oil (AMC No. 8132400) to
system when replacing condenser.
Installation
To install, reverse removal procedure. Fill radiator.
Evacuate, leak test, recharge and check A/C system operation.
Removal (Wrangler)
1) Discharge system (slowly to prevent loss of compressor
oil) using approved refrigerant recovery/recycling equipment. Drain
coolant. Remove fan shroud and radiator. Disconnect pressure line at
condenser. Remove condenser mounting screws. Tilt bottom of condenser
toward engine.
2) From underside of vehicle, disconnect hose attaching
receiver-drier to evaporator. Plug all openings to prevent entry of
dirt or moisture. Remove receiver-drier and condenser assembly. Remove
receiver-drier from condenser.
Installation
To install, reverse removal procedure. Fill radiator.
Evacuate, leak test, recharge and check A/C system operation.
RECEIVER-DRIER
NOTE: On Cherokee, Comanche and Wagoneer, receiver-drier is
removed with condenser and radiator as an assembly.
Removal (Wrangler)
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are continually republished. In addition to these, standards for Drive
Train and Transmissions have recently been promulgated. Participating
shops utilize these Uniform Inspection & Communication Standards as
part of the inspection process and for communicating their findings to
their customers.
The Motorist Assurance Program continues to work
cooperatively and proactively with government agencies and consumer
groups toward solutions that both benefit the customer and are
mutually acceptable to both regulators and industry. We maintain the
belief that industry must retain control over how we conduct our
business, and we must be viewed as part of the solution and not part
of the problem. Meetings with state and other government officials
(and their representatives), concerned with auto repair and/or
consumer protection, are conducted. Feedback from these sessions is
brought back to the association, and the program adjusted as needed.
To assure auto repair customers recourse if they were not
satisfied with a repair transaction, the Motorist Assurance Program
offers mediation and arbitration through MAP/BBB-CARE and other non-
profit organizations. MAP conducted pilot programs in twelve states
before announcing the program nationally in October, 1998. During the
pilots, participating repair shops demonstrated their adherence to the
Pledge and Standards and agreed to follow the UICS in communicating
the results of their inspection to their customers. To put some
"teeth" in the program, an accreditation requirement for shops was
initiated. The requirements are stringent, and a self-policing method
has been incorporated which includes the "mystery shopping" of
outlets.
We welcome you to join us as we continue our outreach... with
your support, both the automotive repair industry and your customers
will reap the benefits. Please visit MAP at our Internet site www.
motorist.org or contact us at:
1444 I Street, NW Suite 700
Washington, DC 20005
Phone (202) 712-9042 Fax (202) 216-9646
January 1999
MAP UNIFORM INSPECTION GENERAL GUIDELINES
OVERVIEW OF SERVICE REQUIREMENTS & SUGGESTIONS
It is MAP policy that all exhaust, brake, steering,
suspension, wheel alignment, drive-line, engine performance and
maintenance, and heating, ventilation and air conditioning, and
electrical services be offered and performed under the standards and
procedures specified in these sections.
Before any service is performed on a vehicle, an inspection
of the appropriate system must be performed. The results of this
inspection must be explained to the customer and documented on an
inspection form. The condition of the vehicle and its components will
indicate what services/part replacements may be "Required" or
"Suggested". In addition, suggestions may be made to satisfy the
requests expressed by the customer.
When a component is suggested or required to be repaired or
replaced, the decision to repair or replace must be made in the
customer's best interest, and at his or her choice given the options
available.
This section lists the various parts and conditions that
indicate a required or suggested service or part replacement.
Although this list is extensive, it is not fully inclusive. In
addition to this list, a technician may make a suggestion. However,
any suggestions must be based on substantial and informed experience,
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\003
AU TO T R AN S D IA G NO SIS - A W 4
1988 J e ep C hero ke e
AUTOMATIC TRANSMISSIONS
Aisin Warner 4 Electronic Diagnosis
APPLICATION
NOTE: Transmission may also be referred to as AW-4.
TRANSMISSION APPLICATION
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Vehicle Application Transmission Model
Jeep
1987-96 Cherokee ................................... AW4
1987-92 Comanche ................................... AW4
1987 Grand Wagoneer ................................ AW4
1987-90 Wagoneer ................................... AW4
1992 Wrangler ...................................... AW4
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NOTE: Vehicle body code may be required when diagnosing or
repairing transmission, as body code may be used instead of
vehicle model name. See BODY CODE DESIGNATION table.
BODY CODE DESIGNATION
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Vehicle Model Body Code
Cherokee .............................................. XJ
Comanche .............................................. MJ
Grand Wagoneer ........................................ SJ
Wagoneer .............................................. XJ
Wrangler .............................................. YJ
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DESCRIPTION
The electronic control system for the AW-4 transmission
controls transmission shift points and torque converter lock-up.
Electronic control system consists of Transmission Control Module
(TCM), valve body solenoids, throttle position sensor, speed sensor,
neutral safety switch and brake switch.
NOTE: Transmission Control Module (TCM) may be referred to as
Transmission Control Unit (TCU). Neutral safety switch may
be referred to as park/neutral safety switch or gear select
switch.
OPERATION
TRANSMISSION CONTROL MODULE (TCM)
The TCM determines shift points and torque converter lock-up
based on input signals received from throttle position sensor, neutral
safety switch, speed sensor and brake switch. The TCM controls
transmission shift points and torque converter lock-up by operating
electric solenoids mounted on the valve body.
The TCM contains a self-diagnostic system used for
determining an electronic component failure. The TCM self-diagnostic
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system will store a diagnostic trouble code in the TCM memory if
certain electronic problems exist. If electronic problem goes away,
diagnostic trouble code will be erased from TCM memory after ignition
has been cycled approximately 75 times.
NOTE: Diagnostic trouble code may be referred to as fault code.
Diagnostic trouble codes can be retrieved using a Diagnostic
Readout Box-II (DRB-II). After repairing an electrical system problem,\
stored diagnostic trouble code must be cleared from TCM memory.
The TCM is located behind right side of instrument panel on
Cherokee. See Fig. 1.
Fig. 1: Transmission Control Module (TCM) I.D. (Cherokee)
Courtesy of Chrysler Corp.
VALVE BODY SOLENOIDS
Valve body solenoids, mounted on the valve body, are output
devices controlled by signals received from the TCM. See Fig. 2. The
No. 1 and 2 valve body solenoids control transmission shifts while the
No. 3 valve body solenoid is used for torque converter lock-up.
When No. 1 and 2 valve body solenoids are energized,
solenoid plunger moves from seat. This opens the drain port and
releases line pressure. When either valve body solenoid is de-
energized, plunger closes the drain port.
The No. 3 valve body solenoid operates in reverse. When No. 3
valve body solenoid is de-energized, solenoid plunger moves away from
seat. This opens the drain port and releases line pressure. When No. 3
valve body solenoid is energized, the plunger closes the drain port.
Page 195 of 1378
![JEEP CHEROKEE 1988 Service User Guide NOTE: For valve body solenoid usage, see VALVE BODY SOLENOID
APPLICATION table.
VALVE BODY SOLENOID APPLICATION (1)
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\](/img/16/57037/w960_57037-194.png "JEEP CHEROKEE 1988 Service User Guide NOTE: For valve body solenoid usage, see VALVE BODY SOLENOID
APPLICATION table.
VALVE BODY SOLENOID APPLICATION (1)
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NOTE: For valve body solenoid usage, see VALVE BODY SOLENOID
APPLICATION table.
VALVE BODY SOLENOID APPLICATION (1)
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Shift Lever No. 1 No. 2
Position Solenoid Solenoid
"D" (Drive)
1st Gear .................. ON .................... OFF
2nd Gear .................. ON ..................... ON
3rd Gear .................. OFF .................... ON
4th Gear .................. OFF ................... OFF
"3"
1st Gear .................. ON .................... OFF
2nd Gear .................. ON ..................... ON
3rd Gear .................. OFF .................... ON
"1-2"
1st Gear .................. ON .................... OFF
2nd Gear .................. ON ..................... ON
"R" (Reverse) .............. ON .................... OFF
"N" Or "P" ................. ON .................... OFF
( 1) - Valve body contains 3 valve body solenoids. See
Fig. 2. No. 1 and 2 valve body solenoids are used
for controlling transmission shifts. No. 3 valve
body solenoid is used for torque converter
lock-up only.
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Fig. 2: Identifying Valve Body Solenoids
Courtesy of Chrysler Corp.
BRAKE SWITCH
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Brake switch is an input device mounted above the brake
pedal. When brake pedal is operated, brake switch delivers an input
signal to the TCM. The TCM uses input signal for controlling No. 3
valve body solenoid for torque converter lock-up.
NEUTRAL SAFETY SWITCH
NOTE: Neutral safety switch may be referred to as park/neutral
safety switch or gear select switch.
Neutral safety switch is an input device mounted on the
transmission manual valve shaft. Neutral safety switch delivers an
input signal to TCM, indicating transmission manual valve gear
position.
SPEED SENSOR
Speed sensor, mounted in adapter housing or extension
housing, is an input device consisting of speed sensor rotor and speed
sensor. Speed sensor rotor is mounted on transmission output shaft.
Input signal is delivered from speed sensor to TCM with each
revolution of transmission output shaft. The TCM uses input signal for
controlling transmission operation.
THROTTLE POSITION SENSOR (TPS)
The TPS, mounted on throttle body, determines throttle
position and delivers an input signal to TCM. The TCM uses input
signal for controlling transmission upshifts and torque converter
lock-up.
SELF-DIAGNOSTIC SYSTEM
DIAGNOSTIC PROCEDURE
When performing vehicle diagnosis:
* Ensure transmission fluid level is correct and fluid is
neither contaminated nor aerated.
* Ensure shift cable is properly adjusted. Refer to the
appropriate TRANSMISSION SERVICING - A/T article in
this section.
* Ensure battery is fully charged.
* Perform visual inspection, ensuring all electrical
connections at transmission, TCM, throttle position sensor,
neutral safety switch, speed sensor and brake switch are
clean and properly installed.
* Perform TEST 1A - VERIFICATION OF THE COMPLAINT under TROUBLE
SHOOTING CHARTS in this article.
* Repair diagnostic trouble codes in order displayed.
* Always perform TEST 2A - VERIFICATION TEST after repair is
completed. See TEST 2A - VERIFICATION TEST under TROUBLE
SHOOTING CHARTS in this article.
RETRIEVING DIAGNOSTIC TROUBLE CODES
NOTE: Manufacturer recommends using Chrysler's Diagnostic Readout
Box-II (DRB-II) with proper cartridge for system diagnosis.
Other after-market scan tools may be used for system
diagnosis. The following procedure is for DRB-II scan tool
usage. Use manufacturer's instruction for operating the
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DRB-II scan tool. When retrieving diagnostic trouble codes
using DRB-II, you must first enter AW4 MENU and then
retrieve diagnostic trouble codes.
NOTE: Ensure TEST 1A - VERIFICATION OF THE COMPLAINT is performed
when trouble shooting the vehicle. This test checks for
diagnostic trouble codes with vehicle stationary and during
road test. See TEST 1A - VERIFICATION OF THE COMPLAINT under
TROUBLE SHOOTING CHARTS.
NOTE: The DRB-II scan tool can be used in several different modes
using manufacturer's instructions to activate system
components and perform several tests on transmission. See
DRB-II OPERATING MODES .
Entering AW4 MENU
1) Ensure ignition is off. Connect DRB-II to 6-pin
transmission diagnostic connector. See Fig. 3. Transmission diagnostic
connector is located to the right of the steering column on driver's
side of instrument panel above accelerator pedal or below glove box on
passenger's side.
Fig. 3: Diagnostic Connector & Terminals I.D. (Cherokee)
Courtesy of Chrysler Corp.
2) Turn ignition on. Copyright date and diagnostic program
will be briefly displayed. If DRB-II displays an error message,
proceed to DRB-II PROBLEMS & ERROR MESSAGES . The following are
possible error messages that may appear.
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* CARTRIDGE ERROR
* HIGH BATTERY
* KEYPAD TEST FAILURE
* LOW BATTERY
* RAM TEST FAILURE
3) If no error messages appear, display will read as follows
after a few seconds: 1) VEHICLES TESTED, 2) HOW TO USE, 3) CONFIGURE
and 4) SELECT SYSTEM.
4) Select 4) SELECT SYSTEM to enter diagnostic system. Once
in SELECT SYSTEM, select 2) TRANSMISSION to enter transmission.
Display will read 1) EATX and 2) AW4.
5) Select 2) AW4. After a few seconds display will change to
read AW4, VERSION 01. After a few seconds, display will read AW4 MENU,
1) SYSTEM TEST and 2) READ FAULTS. If DOWN ARROW is depressed 3 times,\
display will read as follows: 3) STATE DISPLAY, 4) ACTUATOR TESTS and
5) ADJUSTMENTS.
NOTE: The ACTUATOR TESTS and ADJUSTMENTS cannot be used when
diagnosing the AW-4 transmission.
Retrieving Diagnostic Trouble Codes
1) Select 2) READ FAULTS from AW4 MENU. If no diagnostic
trouble code exists, display will read as follows: AW4 FAULTS, NO
FAULTS DETECTED.
2) If diagnostic trouble code exists, the following message
will be displayed: 1 OF 3 FAULTS. This number will vary depending on
number of diagnostic trouble codes stored in the TCM memory.
3) Diagnostic trouble code and message will be displayed.
Press DOWN ARROW key to display next diagnostic trouble code. To
identify diagnostic trouble code, see DIAGNOSTIC TROUBLE CODE
IDENTIFICATION table.
NOTE: See TROUBLE SHOOTING CHARTS to diagnose faults indicated by
trouble codes.
NOTE: Valve body solenoid diagnostic trouble code 700 may appear
in a FAULT PRESENT or FAULT STORED status. Status will be
displayed along with diagnostic trouble code. Diagnostic
trouble code must be diagnosed depending on the status. See
TEST 1A - VERIFICATION OF THE COMPLAINT under TROUBLE
SHOOTING CHARTS.
DIAGNOSTIC TROUBLE CODE IDENTIFICATION
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Trouble Code Problem Area
700 ( 1) .............................. Valve Body Solenoid
702 ......................................... Speed Sensor
703 ............................... ( 2) Gear Select Switch
705 ............................. Throttle Position Sensor
706 ......................................... Brake Switch
707 ..................................... Wrong TCM Or TCU
( 1) - Trouble code may apply to individual valve body
solenoids. Valve body solenoid may be referred to
as S1 for No. 1, S2 for No. 2 and S3 for No. 3.
( 2) - Gear select switch is the same as the neutral
safety switch.
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CLEARING DIAGNOSTIC TROUBLE CODES