2002 ISUZU AXIOM clutch

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±117
Chart A: Magnetic Clutch Does Not work (Cont'd)
StepNo Ye s Value(s) Action
17Is the battery voltage applied between the harness side
connector terminal No.I19±14 and ground?
ÐGo to Step 19Go to Step 18
18Repair an open circuit between terminal No.X8±3 and
I19±14.
Is the action complete?
ÐGo to Step 17Ð
19Is there continuity between the harness side connector
terminal No.X8±1 and PCM (F45)?
ÐGo to Step 21Go to Step 20
20Repair an open circuit between terminal No.X8±1 and
PCM (F45).
Is the action complete?
ÐGo to Step 19Ð
21Is there continuity between the harness side connector
terminal No.X2±4 and PCM (F4)?
ÐGo to Step 23Go to Step 22
22Repair on open circuit between terminal No.X2±4 and
PCM (F4).
Is the action complete?
ÐGo to Step 21Ð
23Is there continuity between the harness side connector
terminal No.I20±4 and ground?
ÐGo to Step 25Go to Step 24
24Repair an open circuit between terminal No.I20±4 and
PCM (S47).
Is the action complete?
ÐGo to Step 23Ð
251. Connect the connector of PCM.
2. Connect the connector terminal No.I19±14 which is
on the harness side on the auto air conditioner
control unit.
Magnetic clutch works?
Ð
Replace the
auto air
conditioner
control unit
Replace the
PCM
CAUTION: T h e r e a r e conditions which air
conditioner system dose not operate except trouble
as follows.
1. The throttle is griater than 90%.
2. The ignition voltage is below 10.5 volts.
3. The engine speed greater than 4500 RPM for 5
seconds or 5400 RPM.
4. The engine coolant temperature (ECT) is greater
than 125
C (257
F).
5. The intake air temperature (IAT) is less than 5
C
(41
F).
6. The power steering pressure switch signals a
high pressure condition.

4A2±2DIFFERNTIAL (REAR)
General Description
The rear axle assembly is of the semi±floating type in
which the vehicle weight is carried on the axle housing .
The center line of the pinion gear is below the center line
of the ring gear (hypoid drive).
All parts necessary to transmit power from the propeller
shaft to the rear wheels are enclosed in a salisbury type
axle housing (a carrier casting with tubes pressed and
welded into the carrier). A removable aluminum cover at
the rear of the axle housing permits rear axle service
without removal of the entire assembly from the vehicle.
The 8.9 inch ring gear rear axle uses a conventional ring
and pinion gear set to transmit the driving force of the
engine to the rear wheels. This gear set transfers this
driving force at a 90 degree angle from the propeller shaft
to the drive shafts.
The axle shafts are supported at the wheel end of the
shaft by a roller bearing.
The pinion gear is supported by two tapered roller
bearings. The pinion depth is set by a shim pack located
between the gear end of the pinion and the roller bearing
that is pressed onto the pinion. The pinion bearing
preload is set by crushing a collapsible spacer between
the bearings in the axle housing.
The ring gear is bolted onto the differential case with 10
bolts.
The differential case is supported in the axle housing by
two tapered roller bearings. The differential and ring gear
are located in relationship to the pinion by using selective
shims and spacers between the bearing and the
differential case. To move the ring gear, shims are deleted
from one side and an equal amount are added to the other
side. These shims are also used to preload the bearings
which are pressed onto the differential case. Two bearing
caps are used to hold the differential into the rear axle
housing.
The differential is used to allow the wheels to turn at
different rates of speed while the rear axle continues to
transmit the driving force. This prevents tire scuffing
when going around corners and prevents premature wear
on internal axle parts.
The rear axle is sealed with a pinion seal, a seal at each
axle shaft end, and by a liquid gasket between the rear
cover and the axle housing.
Limited Slip Differential (LSD)
The axle assembly may be equipped with an limited slip
differential (LSD). It is similar to the standard differential
except that part of the torque from the ring gear is
transmitted through clutch packs between the side gears
and differential case.
The LSD construction permits differential action when
required for turning corners and transmits equal torque to
both wheels when driving straight ahead. However, when
one wheel tries to spin due to a patch of ice, etc., the
clutch packs automatically provide more torque to the
wheel which is not trying to spin.
In diagnosing customer complaints, it is important to
recognize two things:
1. If, both wheels slip, with unequal traction, the LSD
has done all it can possibly do.
2. In extreame cases of differences in traction, the
wheel with the least traction may spin after the LSD
has transferred as much torque as possible to the
non-slipping wheel.
Limited Slip Differntials impose additional requirements
on lubricants, and require a special lubricant or lubricant
additive. Use 80W90 GL±5 LSD lubricant.
Rear Axle Identification
The Bill of Material and build date information(1) is
stamped on the right axle tube on the rearward side.
The axle ratio is identified by a tag(3) which is secured by
a cover bolt. If the axle has limited-slip differntial, it also
will be identified with a tag(2) secured by a cover bolt.
425RX001

4A2±4DIFFERNTIAL (REAR)
Rear Axle Noise
ConditionPossible causeCorrection
Noise in DriveExcessive pinion to ring gear
backlash.Adjust.
Worn pinion and ring gear.Replace
Worn pinion .bearings.Replace.
Loose pinion bearings.Adjust.
Excessive pinion end play.Adjust.
Worn side bearings.Replace.
Loose side bearings.Adjust.
Excessive ring gear run-out.Replace.
Low oil level.Replenish.
Wrong or poor grade oil.Replace.
Bent axle housing.Replace.
Noisy when coastingAxle noise heard when driving will
usually be heard also on coasting,
although not as loud.Adjust or replace.
Pinion and ring gear too tight (audible
when slowing down and disappears
when driving).Adjust.
Intermittent noiseWarped bevel ring.Replace.
Loose differential case bolts.Tighten.
Constant noiseFlat spot on pinion or ring gear teeth.Replace.
Flat spot on bearing.Replace.
Worn pinion splines.Replace.
Worn axle shaft dowel holes.Replace.
Worn hub studs.Replace.
Bent axle shaft.Replace.
Noisy on turnsWorn differential side gears and
pinions.Replace.
Worn differential shaft.Replace.
Worn axle shaft splines.Replace.
Limited Slip Differential
ConditionPossible causeCorrection
Does not lockBroken clutch plates.Replace the clutch plates.
Chatters in turnsLubricant contaminated.Drain lube when hot. Wipe carrier
clean. Refill with lube specified in
Main Data and Specifications at the
end of this section.
Clutch plates dateriorated.Replace clutch plates.
Noise (in addition to normal clutch
engagement)
Broken clutch plates.Replace clutch plates.
engagement)Damaged case.Replace unit.
Broken differential gears.Replace gears.

4A2±28DIFFERNTIAL (REAR)
4. Assemble clutch pack unloading tool .
a. Install cap J±34174±1 to the bottom differential
side gear.
b. Install threaded screw cap J±34174±2 to top
differential side gear. Thread forcing screws
J±22342±15 into threaded screw cap until it
becomes centered into the bottom cap.
901RW153
c. Tighten forcing screw until tight enough to collapse
dished spacers and allow looseness between side
and pinion mate gears.
5. Both pinion mate gear thrust washers using a shim
stock (1) of 0.51 mm (0.020 in.) or equivalent tool to
push out washers.
425RW007
6. Relieve tension of dished spacers by loosening
forcing screw.NOTE:

You may have to adjust the forcing screw slightly to
allow the case to rotate.
7. Assemble LSD service adapter J±39834 onto long
drive handle J±8592.Insert it into differential shaft
hole of case. Pull on handle and rotate case until
pinion mate gears can be removed.
901RW068
8. Remove pinion mate gears.
9. Hold side gear top clutch pack (1) with one hand and
remove positraction unloading tools.
425RW008
10. Remove top side gear and clutch pack.
NOTE:

Keep the stack of plates and discs intact and in
exactly the same position while they are being
removed.
11. Remove case from holder. Turn case with flange or
ring gear side up to allow side gear and clutch pack to
be removed from case.

DIFFERENTIAL (REAR)4A2±29
12. Remove differential plate retainer from both clutch
packs to allow separation of the plates and discs.
NOTE:

Keep the discs and plates in the same order as they
were removed.
425RW009
Legend
(1) Differential Plate
(2) Differential Disc
(3) Dished Spacer
(4) Side Gear
Inspection and Repair
Cleaning

All parts with solvent.
Visual Inspection

Clean all parts with solvent.

Plates and Discs. If any one disc or plate in either
stack shows evidence of excessive wear or scoring,
the complete stack is to be replaced on both sides.

Side Gears and Pinion Mate Gears. The gear teeth of
these parts should be checked for extreme wear and
possible cracks. The external teeth of the side gear,
which retain the concentric groove discs, should also
be checked for wear or cracks.

If replacement of one gear is required due to wear,
etc., then both side gears, pinion mate gears, and
thrust washers are to be replaced.

Differential Shaft. If excessive wear is evident, the
differential shaft should be replaced.

Differential Plate Retainers. If wear is evident on any
one of the differential plate retainers, all four retainers
must be replaced.

Differential Case. If scoring, wear or metal pickup is
evident on the machined surfaces, replacement of
the case is necessary.
Reassembly
1. Lubricate thrust face of side gears, plates and discs
with the proper limited slip rear axle lubricant.
2. Assemble plates and discs in exactly in the same
position as they were removed, regardless of whether
they are new or original.
3. Install differential plate retainer to ears of plates.
NOTE:

Make sure both retainers are Completely seated on
ears of plates.
4. Install clutch pack and side gear into bottom side gear
bore. Make sure clutch pack stays assembled to side
gear splines, and that retainers are completely seated
into pockets of case.
NOTE:

To prevent clutch pack from falling out of case, hold
clutch pack in place by hand while repositioning case
on bench.
5. Install other side gear and clutch pack. Make sure
clutch pack stays assembled to side gear splines, and
retainers are completely seated into pockets of case.
6. Hold clutch pack in position and assemble screw cap
J±34174±2, cap J±34174±1 and forcing screw
J±22342±15. Tighten forcing screw into bottom cap
to hold both clutch packs in position.
7. With tools assembled to case, position case on holder
J±39824 by aligning splines of side gear with those of
shaft. Tighten forcing screw to compress clutch packs
in order to provide clearance for pinion mate gears.
901RW069
8. Install pinion mate gears.

Place the pinion mate gears into the differential 180
degrees apart.

4A2±30DIFFERNTIAL (REAR)
9. While holding gears in place, insert LSD service
adapter J±39834 with long drive handle J±8592 in
differential shaft hole of case. Pull on long drive
handle J±8592 and rotate case, allowing gears to
turn. Make sure that holes in pinion mate gears align
with holes in case.
901RW070

It may be necessary to adjust tension on forcing
screw to rotate case.
10. Tighten forcing screw to compress the clutch packs,
to allow installation of spherical thrust washers.
11. Lubricate spherical thrust washers (2), and assemble
into case (1). Use a small screw driver to push
washers into place. Remove tools.
425RW012
12. Position differential shaft in case and drive in with
hammer. Be sure lock pin hole of differential shaft (5)
is properly aligned to allow installation of lock pin (3).
Be sure that thrust washers and differential pinion
mate gears are aligned with the differential case (4).
Install new lock pin to proper depth using a punch.
Stake metal of case over pin in two places, 180
degrees apart.
425RW013

DIFFERENTIAL (REAR)4A2±33
ILLUSTRATIONTOOL NO.
TOOL NAME
J±39837±1
Disc (2 required)
J±23597±1
Arbor
J±42828
Installer; Pinion bearing
J±21784
Installer; Side bearing
J±39602
Remover; Outer bearing
J±24385±B
Spreader
ILLUSTRATIONTOOL NO.
TOOL NAME
J±39858
Clutch pack unloading
tool kit Includes
J±34174±1/J±34174±2
Screw cap and Cap
J±22342±15
Forcing screw
J±39834
Limited±slip differential
(LSD) service adapter
J±39824
Holder
J±39836
Side bearing preload
master bearings

4B2±1
DRIVE LINE CONTROL SYSTEM (TOD)
AXIOM
DRIVELINE/AXLE
DRIVELINE CONTROL SYSTEM (TOD)
CONTENTS
Service Precaution 4B2±1. . . . . . . . . . . . . . . . . . . . . .
General Description 4B2±2. . . . . . . . . . . . . . . . . . . . .
Transfer Position and Drive Mode 4B2±2. . . . . . . .
TOD Control 4B2±3. . . . . . . . . . . . . . . . . . . . . . . . . .
TOD Indicator Control 4B2±3. . . . . . . . . . . . . . . . . .
Abbreviations 4B2±3. . . . . . . . . . . . . . . . . . . . . . . . .
System Components 4B2±4. . . . . . . . . . . . . . . . . . . .
Parts Location 4B2±4. . . . . . . . . . . . . . . . . . . . . . . .
Front and Rear Speed Sensors 4B2±5. . . . . . . . . .
Electromagnetic Coil 4B2±5. . . . . . . . . . . . . . . . . . .
Multi Plate Disk Clutch Pack 4B2±5. . . . . . . . . . . .
Mechanical Lock Sleeve 4B2±5. . . . . . . . . . . . . . . .
High-Low Planetary Gear Set 4B2±6. . . . . . . . . . .
4H and 4L Switch 4B2±6. . . . . . . . . . . . . . . . . . . . . .
Transfer Connector (12-pin type) 4B2±6. . . . . . . .
Transfer Connector (8-pin type) 4B2±6. . . . . . . . .
TOD Indicator Lamps
(on the instrument panel) 4B2±7. . . . . . . . . . . . . .
Check Lamp 4B2±7. . . . . . . . . . . . . . . . . . . . . . . . . .
TOD ECU 4B2±8. . . . . . . . . . . . . . . . . . . . . . . . . . . .
High-Low Shift Motor 4B2±9. . . . . . . . . . . . . . . . . . .
Motor Position and Encoder Position Code 4B2±10
Encode Position Plate 4B2±10. . . . . . . . . . . . . . . . . .
Shift High Range and Low Range 4B2±10. . . . . . . . Functions of TOD Switch and Indicator
Lamp 4B2±11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TOD Switch and Indication of Drive Mode 4B2±11.
Check Lamp 4B2±13. . . . . . . . . . . . . . . . . . . . . . . . . .
Diagnosis 4B2±14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Information Diagnosis 4B2±14. . . . . . . . . .
Self-diagnosis 4B2±14. . . . . . . . . . . . . . . . . . . . . . . . .
Precautions on Diagnosis 4B2±16. . . . . . . . . . . . . . .
Basic Diagnostic Flow Chart 4B2±18. . . . . . . . . . . . . .
Parts Location 4B2±19. . . . . . . . . . . . . . . . . . . . . . . . . .
Circuit Diagram 4B2±20. . . . . . . . . . . . . . . . . . . . . . . . .
Connector List 4B2±24. . . . . . . . . . . . . . . . . . . . . . . . . .
Checking Failed Pin 4B2±26. . . . . . . . . . . . . . . . . . . . .
Connector Pin Assignment 4B2±26. . . . . . . . . . . . . .
Reference 4B2±28. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking Failed TOD Control Unit Pin 4B2±30. . . . .
Tech 2 Scan Tool 4B2±32. . . . . . . . . . . . . . . . . . . . . .
Getting Started 4B2±33. . . . . . . . . . . . . . . . . . . . . . . .
Operating Procedure 4B2±33. . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Codes 4B2±35. . . . . . . . . . . . . . . .
Diagnosis from Trouble Codes 4B2±36. . . . . . . . . . . .
Trouble Diagnosis Depending on The Status
of TOD Indicator 4B2±67. . . . . . . . . . . . . . . . . . . . . . . .
Diagnosis from Symptom 4B2±102. . . . . . . . . . . . . . . . .
Service Precaution
WARNING: THIS VEHICLE HAS A SUPPLEMENTAL
RESTRAINT SYSTEM (SRS). REFER TO THE SRS
COMPONENT AND WIRING LOCATION VIEW IN
ORDER TO DETERMINE WHETHER YOU ARE
PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING. WHEN YOU
ARE PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING, REFER TO
THE SRS SERVICE INFORMATION. FAILURE TO
FOLLOW WARNINGS COULD RESULT IN POSSIBLE
AIR BAG DEPLOYMENT, PERSONAL INJURY, OR
OTHERWISE UNNEEDED SRS SYSTEM REPAIRS.CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, or other
corrosion inhibitors) on threaded fasteners or
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener. When
you install fasteners, use the correct tightening
sequence and specifications. Following these
instructions can help you avoid damage to parts and
systems.