run flat ISUZU TROOPER 1995 Workshop Manual
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Page 122 of 1928

3-2 DIAGNOSIS
GENERAL DIAGNOSIS
Condition Possible Cause Correction
Vehicle
Pulls 1. Mismatched or uneven tires. Replace tire.
2. Tires not adequately inflated. Adjust tire pressure.
3. Broken or sagging springs. Replace spring.
4. Radial tire lateral force. Replace tire.
5. Improper wheel alignment. Adjust wheel alignment.
6. Brake dragging in one wheel. Repair brake.
7. Loose, bent or broken front or rear suspension Tighten or replace the
parts. appropriate suspension
part(s).
8. Faulty shock absorbers. Replace shock absorber.
Abnormal or Excessive 1. Sagging or broken spring. Replace spring.
Tire Wear
2. Tire out of balance. Balance or replace tire.
3. Improper wheel alignment. Check front end alignment.
4. Faulty shock absorber. Replace shock absorber.
5. Hard driving. Replace tire.
6. Overloaded vehicle. Replace tire
and reduce
load.
7. Tires not rotated periodically. Replace or rotate
tire.
8. Worn or loose road wheel bearings. Replace wheel bearing.
9. Wobbly wheel or tires. Replace wheel or tire.
10. Tires not adequately inflated. Adjust the pressure.
Wheel Tramp or Hop 1. Blister or bump on tire. Replace tire.
2. Improper shock absorber operation. Replace shock absorber.
Shimmy,
Shake or 1. Tire or wheel out of balance. Balance
wheels or replace
Vibration tire/or wheel.
2. Loose wheel bearings. Replace wheel bearing.
3. Worn steering linkage ball joints. Replace ball joints.
4. Worn upper or lower end ball joints. Replace ball joints.
5. Excessive wheel runout. Repair or replace
wheel
and/or tire.
6. Blister or bump on tire. Replace tire.
7. Excessive loaded radial runout of tire/wheel Replace tire or wheel.
assembly.
8. Improper wheel alignment. Check
wheel alignment.
9. Loose or worn steering linkage. Tighten or replace steering
linkage.
10. Loose steering gear. Tighten
housing bolts.
11. Tires not adequately inflated. Adjust tire pressure.
12. Loose, bent or broken front or rear Tighten or replace the
suspension parts. appropriate suspension
parts.
13. Faulty shock absorber. Replace shock absorber.
14. Hub bearing preload misadjustment. Adjust preload.
Hard Steering 1. Bind in steering linkage ball studs, upper or Replace ball joint.
lower end ball joint.
2. Improper wheel alignment. Check wheel alignment.
3. Steering gear misadjustment. Check and adjust pinion
torque.
4. Tire not adequately inflated. Inflate tires to proper
pressure.
5. Bind in steering column or shaft. Repair or replace.
6. Improper power steering
system operation. Repair or replace.
Refer to "Power steering
system diagnosis"
'· •
Page 124 of 1928

3-4 DIAGNOSIS
Condition Possible Cause Correction
Erratic Steering When 1. Worn wheel bearings. Replace wheel bearings.
Braking
2. Broken or sagging springs. Replace spring (pairs).
3. Leaking caliper. Repair or replace caliper.
4. Warped discs. Replace brake disc.
5. Badly worn brake pads. Replace brake pads.
6. Tires are inflated unequally. Inflate tires to proper
pressure.
Low or Uneven Trim
1. Broken or sagging springs. Replace springs (In pairs)
Height
2. Vehicle overloaded. Reduce load.
3. Incorrect springs. Adjust or replace torsion
bar.
Suspension Bottoms
1. Vehicle overloaded. Reduce load.
2. Faulty shock absorber. Replace shock absorber
3. Incorrect, broken or sagging springs. Replace springs.
Body Leans
1. Loose stabilizer bar. Tighten stabilizer bar bolts
or replace bushings.
2. Faulty shock
absorber, struts or mounting. Replace shock absorber.
3. Broken or sagging springs. Replace springs (In pairs)
4. Vehicle overloaded. Reduce load.
Cupped Tires 1. Worn wheel bearings. Replace wheel bearing.
2. Excessive tire or wheel run-out. Replace tire or wheel.
3. Worn ball joints. Replace ball joints.
4. Tire out of balance. Adjust tire balance.
•
Page 135 of 1928

FRONT END ALIGNMENT 3A-3
ON-VEHICLE SERVICE
INSPECTION
Before making any adjustments affecting caster,
camber or toe-in, the following front end inspection
should be made.
I L•IINSPECT
1. Tires for proper inflation pressure. Refer to
"Wheels and Tires" in section 3E.
2. Front wheel bearings for proper adjustment.
Refer to "Front Wheel Drive" in section 4C.
3. Ball joints, tie rod ends and relay rods. If
excessive looseness is noted, correct before
adjusting. Refer
to "Steering Linkage" in section
3B3.
4. Wheel and tires for run-out. Refer to "Wheels
and Tires" in section 3E.
5. Trim height. If not within specifications, the
correction
must be made before adjusting caster.
6. Steering gear for looseness at the frame.
7. Shock absorbers for leaks or any noticeable
noise.
Refer
to "Front Suspension" in section 3C.
8. Control arms or stabilizer bar attachment for
looseness. Refer to "Front Suspension" in section
3C.
9. Alignment equipment. Follow the manufacturer's
instructions.
10. Level of the vehicle. The vehicle must be on a
level surface.
TRIM HEIGHT ADJUSTMENT
Adjust the trim height by means of the adjusting bolt
on the height control arms (Fig. 3A-4 and 5).
W CAUTION:
When adjusting front end alignment, be sure to
begin with trim height as trim height adjustment
may change other adjusted alignments.
1. Check and adjust the tire inflation pressures.
2. Park the vehicle on a level ground and move the
front of the vehicle up and down several times to
settle the suspension.
3. Make necessary adjustment with the adjusting
bolt on the height control arms.
WHEEL
ALIGNMENT SPECIFICATION
Trim height (Z) 129 mm (5.08 in)
Lower
ball joint
B
Fig. 3A-4
Fig. 3A-5
CASTER ADJUSTMENT
Level ground
The caster angle can be adjusted by means of the
caster shims installed between the chassis frame and
fulcrum pins (Fig. 3A-6 and 7).
WHEEL
ALIGNMENT SPECIFICATION
LWB
Caster angle
SWB
W CAUTION:
Left and right side to be equal within 30'
NOTE:
Difference of the caster shim front/rear thickness shall
be 3.6
mm (0.142 in) or less. Overall thickness of caster
shim and camber shim shall be 10.8 mm (0.425 in) or
less.
Page 207 of 1928

WHEELS AND TIRES 3E-1
TIRES
REPLACEMENT
UNIT REPAIR
WHEELS
REPLACEMENT
When replacement is necessary, the original metric
the size should be used. Most metric tire sizes do not
have exact corresponding alphanumeric tire sizes. It
is recommended that new tires be installed in pairs on
the same axle. If necessary to replace only one tire, it
should be paired with tire having the most tread, to
equalize braking traction.
w CAUTION:
Do not mix different types of tires such as radial,
bias and bias-belted tires except in emergencies,
because
vehicle handling may be seriously
affected and may result in loss of control.
TIRE DISMOUNTING
Remove valve cap on valve step and deflate the tire.
Then use a
tire changing machine to mount or
dismount tires.
Follow the equipment manufacturer's instruction. Do
not use hand tools or tire lever alone to change tires
as they may damage the tire beads or wheel rim.
TIRE MOUNTING
Rim bead seats should be cleaned with a wire brush
....._., or coarse steel wool to remove lubricants, and light
rust. Before mounting a tire, the bead area should be
well lubricated with an approved tire lubricant.
After mounting, inflate the tire to 196kPa (28 psi) so
that beads are completely seated. Inflate the air to
specified pressure and install valve cap to the stem.
\f WARNING:
Never stand over tire when inflating. Bead may
break when bead snaps over rim's safety hump
and cause serious personal injury.
Never exceed
240 kPa (35 psi) pressure when
inflating. If 240 kPa (35 psi) pressure will not
seat beads, deflate, re-lubricate and re-inflate.
Over
inflation may cause the bead to break and
cause serious
personal injury.
TIRE REPAIR
There are many different materials on the market
used to repair tires.
Manufacturers have published detailed instructions
on how and when to repair tires. These instructions
can be obtained from the tire manufacturer if they are
not included with the repair kit. Damaged
wheels and wheels with excessive run-out
must be replaced.
Fig. 3E-10
Wheel
run-out at rim
Steel Aluminum
@ Vertical play: 1.5 (0.059) 0.7
(0.028) Less than mm(in)
@ Horizontal play: 1.5 (0.059) 0.7
(0.028) Less than mm(in)
Page 245 of 1928

REAR AXLE 48-3
DIAGNOSIS OF REAR AXLE NOISE
Many noises that seem to come from the rear axle
actually
originate from other sources such as tires,
road surface, wheel bearings, engine, transmission,
muffler,
or body drumming. Investigate to find the
source
ofthe noise before disassembling the rear axle.
Rear axles,
like any other mechanical device, are not
absolutely quiet but should be considered quiet unless
some abnormal noise is present.
To make a systematic check
for axle noise, observe the
following:
1. Select a level asphalt road to reduce tire noise and
body drumming.
2. Check rear axle lubricant level to assure correct
level, and then drive the vehicle far enough to
thoroughly warm up the rear axle lubricant.
3. Note the speed at which noise occurs. Stop the
vehicle and put the transmission in neutral. Run
the engine speed
slowly up and down to
determine if the noise is caused by exhaust,
muffler noise, or other engine conditions.
4. Tire noise changes with different road surfaces;
axle noises do not. Temporarily inflate all tires to
344
kPa (50 psi) (for test purposes only). This will
change noise caused by tires but will not affect
noise caused by the rear
axle.
Rear axle nose usually stops when coasting at
speeds under
48 km/h (30 mph); however, tire
noise continues
with a lower tone. Rear axle noise
usually changes when comparing pull and coast,
but tire noise stays about the same.
Distinguish between tire noise and rear
axle noise
by noting
if the noise changes with various
speeds
or sudden acceleration and deceleration.
Exhaust and
axle noise vary under these
conditions,
while tire noise remains constant and
is more pronounced at speeds
of 32 to 48 km/h
(20 to 30 mph). Further check for tire noise by
driving the vehicle
over smooth pavements or dirt
roads (not gravel) with the tires at normal
pressure.
If the noise is caused by tires, it will
change noticeably with changes in road surface.
5. Loose or rough front wheel bearings will cause
noise
which may be confused with rear axle
noise; however, front wheel bearing noise does
not change when comparing drive and coast.
Light application
of the brake while holding
vehicle speed steady
will often cause wheel
bearing noise to diminish. Front wheel bearings
may be checked for noise by jacking up the
wheels and spinning them
or by shaking the
wheels
to determine if bearings are loose.
6. Rear suspension rubber bushings and spring
insulators dampen
out rear axle noise when
correctly installed. Check to see that there is no
link or rod loosened or metal-to-metal contact.
7. Make sure that there is no metal-to-metal contact
between the
floor and the frame.
After the noise has been determined to be in the axle,
the type of axle noise should be determined, in order to
make any necessary repairs.
GEAR NOISE
Gear noise (whine) is audible from 32 to 89 km/h (20 to
55 mph) under four driving conditions.
1. In drive under acceleration or heavy pull.
2. Driving under load or under constant speed.
3. When using enough throttle to keep the vehicle
from driving the engine while the vehicle slows
down gradually (engine still pulls slightly).
4. When coasting with the vehicle in gear and the
throttle closed. The gear noise is
usually more
noticeable between 48 and 64
km/h (30 and 40
mph) and 80 and 89 km/h (50 and 55 mph).
BEARING NOISE
Bad bearings generally produce a rough growl or
grating sound, rather than the whine typical of gear
noise. Bearing noise frequently
"wow-wows" at
bearing rpm, indicating a bad pinion
or rear axle side
bearing. This noise can
be confused with rear wheel
bearing noise.
REAR WHEEL BEARING NOISE
Rear wheel bearing noise continues to be heard while
coasting at low speed with transmission in the neutral.
Noise may diminish by gentle braking. Jack up the rear
wheels, spin them by hand and
listen for noise at the
hubs. Replace any faulty
wheel bearings.
KNOCK AT LOW SPEEDS
Low speed knock can be caused by worn universal
joints or a side gear hub counter bore in the cage that is
worn oversize. Inspect and replace universal joints or
cage and side gears as required.
BACKLASH CLUNK
Excessive clunk on acceleration and deceleration can
be caused by a worn rear axle pinion shaft, a worn
cage, excessive clearance between the axle and the
side gear splines, excessive clearance between the
side gear hub and the counterbore in the cage,
worn
pinion and side gear teeth, worn thrust washers, or
excessive drive pinion and ring gear backlash.
Remove
worn parts and replace as required. Select
close-fitting parts when possible. Adjust pinion and
ring gear backlash.
Page 322 of 1928

SA-2 HYDRAULIC BRAKES
BRAKE SYSTEM DIAGNOSIS
ROAD TESTING THE BRAKES
Brake Test
Brakes should be tested on a dry, clean, reasonably
smooth and
level roadway. A true test of brake
performance cannot be made
if the roadway is
wet, greasy
or covered with loose dirt so that all
tires do not grip the road equally. Testing will also
be adversely affected if the roadway is crowned so
as to throw the weight of the vehicle toward
wheels on one side or if the roadway is so rough
that wheels tend to bounce. Test the brakes at dif
ferent vehicle speeds with both light and heavy
pedal pressure; however, avoid locking the wheels
and sliding the tires. Locked wheels and sliding
tires do not indicate brake efficiency, since heavily
braked but turning wheels will stop the vehicle in
less distance than locked wheels. More tire-to-road
friction is present
with a heavily braked turning tire
then
with a sliding tire.
The standard brake system is designed and
balanced
to avoid locking the wheels except at very high
deceleration
levels.
It
is designed this way because the shortest stopping
distance and best
control is achieved without brake
lock-up.
Because of high deceleration capability, a firmer pedal
may be felt at higher deceleration levels.
External Conditions That Affect Brake
Performance
1.
2.
3.
Tires: Tires having unequal contact and grip on
the road
will cause unequal braking. Tires must
be equally inflated, identical in size, and the tread
pattern
of right and left tires must be approxi
mately equal.
Vehicle loading:
A heavily loaded vehicle requires
more braking effort.
Wheel Alignment: Misalignment of the wheels,
particularly
in regard to excessive camber and
caster,
will cause the brakes to pull to one side.
BRAKE FLUID LEAKS
With engine running at idle and the transmission in
"Neutral", depress the brake pedal and hold a constant
foot pressure on the pedal. If pedal gradually falls
away with the constant pressure, the hydraulic system
may be leaking.
Check the master cylinder fluid level. While a slight
drop in reservoir level will result from normal lining
wear, an abnormally low level in reservoir indicates a
leak in the system. The hydraulic system may be
leaking internally as well as externally. Refer to
"Master Cylinder Inspection". Also, the system may
appear
to pass this test but still have slight leakage. If
fluid level
is normal, check the vacuum booster
push rod
length. If an incorrect length push rod is
found, adjust
or replace the push rod. Check the
brake
pedal travel and the parking brake adjust
ment.
When checking the
fluid level, the master cylinder fluid
level
may be low from the "MAX" mark if the front and
rear
linings are worn. This is not abnormal.
WARNING LIGHT OPERATION
When the ignition switch is in the START position,
the
"BRAKE" warning light should glow and go off
when the ignition switch returns to the ON position.
The
following conditions will activate the "BRAKE"
light:
1. Parking brake applied. The light should be on
whenever the parking brake is applied and the
ignition switch is on.
2. Low fluid level. A low fluid level in the master
cylinder will turn the "BRAKE" light on (Except
Rear
Wheel Antilock Brake System (RWAL)
model).
3. During engine cranking the "BRAKE" light
should
remain on. This notifies the driver that
the warning circuit is operating properly.
4. In the event of a front or rear system malfunc
tion (RWAL model only).
5. In the event of RWAL malfunction (RWAL
model only. Refer to Section 5A3).
ANTILOCK BRAKE SYSTEM (RWAL or
ABS}
Refer to Section 5A3 or 5A4 for inspection and di
agnosis procedure of the hydraulic unit.
..
Page 323 of 1928

HYDRAULIC BRAKES 5A-3
DIAGNOSIS OF BRAKE SYSTEM
Condition
Possible Cause Correction
Brake
Pull 1. Tire inflation pressures unequal. 1. Adjust
2. Front wheel alignment incorrect. 2. Adjust
3. Unmatched tires on same axle. 3. Tires with approx. the same amount of
tread should be used on the same axle.
4. Restricted brake pipes or hoses. 4. Check for soft hoses and damaged
lines. Replace with new hoses and new
double-walled steel brake piping.
5. Water or oil on brake pads. 5. Clean or replace.
6. Brake pads hardened. 6. Replace.
7. Brake pads worn excessively. 7. Replace.
8. Brake rotor worn or scored. 8. Grind or replace.
9. Disc brake caliper malfunctioning. 9. Clean or replace.
10. Front hub bearing preload incorrect. 10. Adjust or replace.
11. Loose suspension parts. 11. Check all suspension mountings.
12. Loose
calipers. 12. Check and tighten bolts to specifi-
cations.
Brake 1. Excessive lateral runout. 1. Check per instructions.
Roughness-or If not within specifications, replace or
Chatter machine the rotor.
(Pulsates) 2. Parallelism not within specifications. 2. Check per instructions.
If not within specifications, replace or
machine the rotor.
3. Wheel bearings not adjusted. 3. Adjust wheel bearings to correct
specifications.
4. Pad reversed (steel against iron). 4. Replace brake pad and machine rotor
to within specifications.
Excessive Pedal 1. Malfunctioning vacuum booster. 1. Check vacuum booster operation and
Effort repair, if necessary.
2. Partial system failure. 2. Check front and rear brake system for
failure and repair. Also, check brake
warning
light. If a failed system
is
found, the
light should indicate a
failure.
3. Excessively worn pad. 3. Check and replace pads in sets.
4. Piston in caliper stuck or sluggish. 4. Remove caliper and rebuild.
5. Fading brakes due to incorrect pad. 5. Remove and replace with original
equipment pad or equivalent.
6. Vacuum leak to vacuum booster. 4. Check for ruptured or loose hose.
7. Check direction of check valve within 5. Correct vacuum hose direction.
vacuum hose.
8. Grease on the brake pads. 6. Replace or clean.
Excessive Brake 1. Air in hydraulic circuit. 1. Bleed hydraulic circuit.
Pedal Travel 2. Level of brake fluid in reservoir too low. 2. Replenish brake fluid reservoir to speci-
fied
level and bleed hydraulic circuit as
necessary.
3. Master cylinder push rod clearance ex-3. Adjust.
cessive.
4. Leakage in hydraulic system. 4. Correct or replace defective parts.
Page 331 of 1928

INSPECTION OF BRAKE PAD LINING
(Fig. SA-6)
Inspect the brake linings any time the wheels are
removed (tire rotation, etc.). Check both ends
of the
outer pad by
looking at each end of the caliper. These
are the points at which the highest rate
of wear
normally occurs. At the same time, check the lining
thickness on the inner shoe to make sure that it was not
worn prematurely. Some inboard shoes and linings
have a thermal layer against the shoe, integrally
molded
with the lining. This extra layer should not be
confused with uneven inboard-outboard lining wear.
Look
down through the inspection hole in the top of the
caliper to view the inner shoe. Whenever the thickness
of any lining is worn to within 1 mm (0.039 in) of the
shoe,
all disc brake pad and lining assemblies should
be replaced at the same time.
The disc pads have a
wear indicator that makes a noise
when the pad wear to a degree where replacement is
required.
100
Limit 11.0 mm (0.039 in) I
Fig. 5A-6
INSPECTION OF BRAKE ROTORS
In manufacturing the brake rotor, tolerances of the
braking surfaces
for flatness, parallelism and lateral
runout are held very close. The maintenance of close
tolerance
on the shape of the braking surfaces is
necessary to prevent brake roughness.
In addition to these tolerances, the surface finish must
be held to a specified range. The control ofthe braking
surface finish is necessary to avoid
pulls and erratic
performance and to extend
lining life.
Light scoring of the rotor surfaces not exceeding
0.38mm (0.015 in) in depth, which may result from
normal use, is not detrimental to brake operation.
Thickness Variation Check (Fig. 5A-7)
1. Thickness variation can be checked by measuring
the thickness
of the rotor at four or more points
around the circumference
of the rotor. All
measurements must be made at 29 mm (1.14 in)
front/22 mm (0.87 in) rear from the edge of the
rotor.
HYDRAULIC BRAKES 5A-11
Fig. 5A-7
~~~ Front Disc Brake Rotor Thickness
Standard mm (in) 26.0 (1.024)
Limit mm(in) 24.6 (0.969)
~~~Rear Disc Brake Rotor Thickness
Standard mm (in) 18.0 (0.709)
Limit mm (in) 16.6 (0.654)
2. A rotor that varies by more than 0.010 mm
(0.0004 in) can cause pedal pulsation and/or front
end vibration during brake applications. A rotor
that does not meet these specifications should be
refinished
to specifications or replaced.
Lateral Runout Check (Fig. 5A-8)
1. Adjust the wheel bearing correctly.
• Refer to "Front Drive Axle" in Section 4C.
2. Install 2 wheel nuts to retain rotor.
3. Fasten a dial indicator to the suspension so that
the indicator stylus contacts the rotor about
29 mm (1.14 in)-front/22 mm (0.87 in)-rear from
the rotor edge.
4. Zero the dial indicator.
5. Move the rotor one complete revolution and
observe
total indicated runout.
Fig. 5A-8
Page 874 of 1928

7A-2 AUTOMATIC TRANSMISSION (4L30-E)
Valve Body Assembly (Adapter Case) ....... 7A-168 Third Clutch and Sprag Unit ....................... 7A-195
Transmission Control
Module (TCM) ......... 7A-169 Third Clutch .................................................. 7A-196
Speed Sensor (Extension Housing) ............ 7A-169 Sprag
Unit ....................................................
7A-198
Transmission
Oil Temperature Sensor Second
Clutch .............................................. 7A-199
(Adapter Case) ..........................................
7A-170 3-4 Accumulator Piston ............................... 7A-200
Front Oil Seal (Converter Housing) ............ 7A-170 Reverse Clutch Piston and Center
Rear
Oil Seal (Extension Housing) ............. 7A-171 Support ..................................................... 7 A-202
Unit Repair ........................................................ 7A-173 Overrun Clutch and Turbine Shaft ............. 7A-204
Transmission (4L30-E) ................................. 7A-173 Main Data and Specifications ......................... 7 A-207
Converter Housing and Oil Pump General
Specifications ................................. 7 A-207
Assembly .................................................. 7 A-189 Torque
Specifications .................................. 7A-208
Oil
Pump ....................................................... 7A-190 Special Tools .................................................... 7A-211
Main Case Valve Body ................................. 7A-191 4L30-E Parts List.. ............................................. 7A-213
Adapter Case Valve Body ............................ 7A-193 Hydraulic
Circuit Diagram .......... End of This Manual
GENERAL DESCRIPTION
The 4L30-E is a 4-speed fully-automatic transmission.
It uses a microcomputer as a control unit to judge
running conditions
including throttle opening rate
and vehicle speed, then
it sets the shifting point in
the
optimum timing so that best driving performance
can be achieved.
In addition, the built-in shift mode select function can
select three shift modes according to the driver's
preference.
• Normal mode-Normal shift pattern.
• Winter mode-Starts in 3rd gear to reduce
slippage on ice
or snow.
• Power mode has a delayed upshift for when
more powerful acceleration is required.
Also, the built-in fail-safe
function ("backup mode")
assures driving performance even if the vehicle
speed sensor,
throttle signal or any solenoid fails.
Further, the self-diagnostic
function conducts diag
nosis in a short time when the control system fails,
thus improving serviceability.
The major features of 4L30-E are as follows:
• A compact structure consisting of 2 sets of
planetary gears and flat torque converter.
• Electronic control selects the optimum shift
mode according
to the driving conditions.
• Electronic control maintains the optimum hy
draulic pressure for clutch, band brake as well as
transmission so that shift feeling is improved.
• Two sets of planetary gears reduce friction of
power train.
Also, a lock-up mechanism in the torque con
verter reduces fuel consumption.
• Wide gear ratio and high torque rate of torque
converter provide
excellent starting perform
ance.
MODEL YEAR 1994-95 CHANGES
The Transmission Control Module (TCM) for ISUZU
TROOPER
models equipped with 4L30-E is changed
from "BOSCH" to "DELCO ELECTRONICS"
manufacture.
The main differences
which will be encountered
while servicing concerned vehicles are as follows:
Diagnostic Trouble Codes (DTC):
DTC's are changed: For example, DTC for
transmission gear error will be as follows depending
on the TCM unit:
-
On the "DELCO" unit (1994-95) ......... DTC 61
-On the "BOSCH" unit (1993-prior) ..... DTC 41
TCM Pin Connector:
The pin connector is changed. Therefore the
connections
to be made for troubleshooting also
change.
Shift Alteration when TECH 1 Tool is connected
toTCM:
SHIFTS WILL BE HARSH WHEN TECH 1 IS
CONNECTED.
Connection of TECH 1 automatically forces maximum
line pressure during shifts only.
Normal line pressure checks at idle and stall spe
can be carried out.
/
/
I J I
/
l
•
Page 1572 of 1928

8-382 CHASSIS ELECTRICAL
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)-AIR BAG
The system consists of the starter switch, Diagnostic Energy Reserve Module (OERM), dual pole arming
sensor,
SRS coil assembly, inflator module (driver & passenger), forward sensor and warning light.
SRS is mainly comprised of the deployment loop and the DERM.
The main function of the deployment loop is to flow current into the inflator modules inside the steering
wheel (driver side) and the passenger side instrument panel (passenger side) to inflate the air bag. The
forward sensor
(LH and /or RH) gets activated by a shock caused by collision during running of a vehicle, the
current
from the battery flows into the inflator modules through dual pole arming sensor, so that the air bag
is
inflated.
The DERM supplies the current to the deployment loop to ensure that the air bag is inflated, if the power
circuit between battery and deployment loop is cut off by the shock of collision.
In
addition, the DERM monitors a voltage drops between components, and if the voltage drops below the
specified
value, the driver is alerted by the "AIR BAG" warning light in meter assembly.
Refer to Section 9J "SUPPLEMENTAL RESTRAINT SYSTEM (SRS)-AIR BAG" for details.
OPERATION OF THE CIRCUIT
DRIVER
INFLATOR MODULE
FOWARD
SENSOR-LH
D
D
STARTER SW
D
1
DUAL POLE ARMING SENSOR
PASSENGER
INFLATOR
MODULE
FORWARD
SENSOR-RH
NOTE: Arrow marks "c::::>" indicate the direction of current
Fig. 8-438
•