automatic transmission ISUZU TROOPER 1995 Service Manual

7 A-24 AUTOMATIC TRANSMISSION (4l30-E)
MECHANICAL/HYDRAULIC DIAGNOSIS SYMPTOMS INDEX
rr PERFORM PRELIMINARY INSPECTION FIRST! , -
CHART SYMPTOMS PAGE
1
NO ENGINE START IN NEUTRAL OR PARK 7A-25
2
NO FORWARD GEARS IN ANY RANGE/NO REVERSE 7A-26
3
NO ENGINE BRAKE IN ANY RANGE 7A-27
4
POOR SHIFTING IN ALL GEARS (ALL HARSH OR ALL SOFT) 7A-28
Sa DELAYS IN DRIVE AND REVERSE 7A-29
5b DELAYS
IN REVERSE ONLY
6 DIAGNOSTIC TROUBLE CODE (DTC) 61 7A-30
7 HARSH 1-2
SHIFT 7A-31
8 HARSH 3-4
SHIFT
9a 3-2 DOWNSHIFT
COMPLAINT
9b HARSH SHIFT WHEN SHIFTING INTO "D" OR ACCELERATING 7A-32 FROM STOP
9c COASTDOWN HARSH SHIFT OR CLUNK AT 3-2 DOWNSHIFT
10 INTERMITTENT 4TH TO 2ND GEAR DOWNSHIFT AT STEADY SPEED 7A-33
11 ENGINE FLARE AT SHIFTING
DURING TURNING ONLY 7A-34
12 ENGINE FLARE DURING 1-2 OR 2-3 SHIFT
13 SHUDDER ONLY DURING TORQUE CONVERTER CLUTCH (TCC) APPLYING 7A-35
14
POSSIBLE CAUSES OF TRANSMISSION NOISE 7A-36
15a
POSSIBLE CAUSES OF LOW LINE PRESSURE 7A-37
15b
POSSIBLE CAUSES OF HIGH LINE PRESSURE 7A-38
16
POSSIBLE CAUSES OF TRANSMISSION FLUID LEAKS It 7A-39
= -NOTE:
Numbers with parenthesis on the following charts refer to Parts List at end of this ~n.
•

AUTOMATIC TRANSMISSION (4L30-E) 7 A-25
CHART 1: NO ENGINE START IN NEUTRAL OR PARK
PERFORM PRELIMINARY INSPECTION FIRST!
NO ENGINE START IN NEUTRAL
When shift lever moved from drive to neutral mostly in hot condition
Does
engine
also not start in neutral when
shift lever moved from
park to neutral?
NO
Open
in neutral
start circuit of mode
switch (63)
Replace mode switch (63)
( ) Refer
to Parts List at the end of this Section.
YES
NO START IN P
(Any condition)
Check mode
switch
(63) setting.
Readjust
if necessary. Problems fixed?
(~e 7 A-'Hi'1':')
NO
YES ~ ~----l~~

7 A-26 AUTOMATIC TRANSMISSION (4L30-E)
CHART 2: NO FORWARD GEARS IN ANY RANGE/NO REVERSE
PERFORM PRELIMINARY INSPECTION FIRST!
Normal line pressure
Check
internal linkage: -Manual linkage (58) not moving manual valve (326)
Check for internal mechanical damage:
-Turbine shaft (506) broken loose -Overrun roller clutch (516) broken loose -Etc.
( l Refer to Parts List at the end of this Section. Check
line pressure Low line pressure
( Refer
to Line
Pressure chart) irt·~~n.
Use CHART 15a: POSSIBLE CAUSES OF LOW LINE PRESSURE ~e ~7

AUTOMATIC TRANSMISSION (4l30-E) 7 A--27
CHART 3: NO ENGINE BRAKE IN ANY RANGE
PERFORM PRELIMINARY INSPECTION FIRST!
Normal line pressure
Check for overrun clutch leaks caused
by:
-Damaged piston lip (513)
-Check ball defective (504)
Check for overrun lockout valve (705) stuck by foreign material
Check
for leaks at turbine shaft (506) Caused by: -Teflon seal rings damaged (508) -Excessive wear of turbine shaft
bearing surfaces
( ) Refer to Parts List at the end
of this Section.
Check
line pressure
(Refer
to Line
Pressure chart) irT'ti'lis Seetit>n.
Low line pressure
Use CHART 15a:
POSSIBLE CAUSES
OF LOW LINE PRESSURE eA fJ'Iil9&
~

7A-28 AUTOMATIC TRANSMISSION (4L30-E)
CHART 4: POOR SHIFTING IN ALL GEARS (ALL HARSH OR ALL SOFT)
PERFORM PRELIMINARY INSPECTION FIRST!
Low line pressure
Use CHART 15a: POSSIBLE CAUSES OF LOW LINE PRESSURE~e ~
NOTE:
(Refer to Line
Pressure chart) i""~Ais Sec+ioo.
Check
line
pressure
Check for these conditions which could affect clutch apply time:
• Defective band apply solenoid (323)
• Defective servo or/and accumulator piston
• Excessive clutch piston travel
Check
of possible causes of internal
leaks:
-Cut or damaged sealing ring(s) -Damaged sealing gasket {s) -Check ball missing or out of
location in 2nd and 3rd clutch pistons
Check for causes of burned clutch
plates or band High
line pressure
Use CHART 15b: POSSIBLE
CAUSES OF HIGH LINE PRESSURE~e ·-M-38.
When TECH1 is connected, line pressure will be at
maximum during shifts.
( ) Refer to Parts List at the end of this Section.

AUTOMATIC TRANSMISSION (4L30·E) 7 A-29
CHART 5a: DELAYS IN DRIVE AND REVERSE
PERFORM PRELIMINARY INSPECTION FIRST! I
Normal line pressure
More than 3 second delay in drive and
reverse with engine off 1 hour or less
Teflon seals (508) on turbine shaft damaged
Check
line pressure
NOTE: A short delay (less than 3
seconds) when first engaging drive or
reverse after allowing vehicle to sit overnight is normal.
1 Refer to Line Pressure chart) I il'fti'1is Section.
Low line pressure
Use CHART 15a:
POSSIBLE CAUSES
OF
LOW LINE PRESSURE OR-page 1-A,.31_
CHART 5b: DELAYS IN REVERSE ONLY
PERFORM PRELIMINARY INSPECTION FIRST!
Normal line pressure
Main case to valve body gasket (88) damaged
Reverse check ball (85) in valve body (84) missing or out of location
( ) Refer to Parts List at the end of this Section.
Check
line pressure (
Refer
to Line
Pressure chart) iii this Section.
Low line pressure
Use CHART 15a:
POSSIBLE CAUSES OF LOW LINE PRESSURE aa..page
~7
Check for restrictions at valve body transfer plate orifice

7 A-30 AUTOMATIC TRANSMISSION (4L30-E)
CHART 6: DIAGNOSTIC TROUBLE CODE (DTC) 61
PERFORM PRELIMINARY INSPECTION FIRST!
I
I
DTC 61 sets.
Check line pressure
Normal line pressure
1 Refer to Line Pressure chart) i" this Seetien.
J
Low line pressure
Use
CHART 15a: POSSIBLE CAUSES
OF LOW LINE PRESSURE~
~
1st and 2nd gear missing or 3rd and 4th gear
missing 1st
and 4th gear missing or 2nd and 3rd gear
missing I
DTC 61 is set in "D" range I 1st gear above 3500 rpm
DTC 61 is set in "D" range
3rd gear between 55-80
mph*
I
Check appropriate shift valve Check
If
OK replace solenoid 1-2/3-4 shift solenoid stuck. YES Replace 1-2/3-4 shift 3rd
gear in
"D" in winter mode.
solenoid.
No engine brake in any
range
(All ranges in Drive &
Reverse are OK)
Check for suspected conditions modifying delays to clutch apply:
-Overrun clutch seal damaged
-Excessive overrun clutch piston travel
-Defective 3-4 accumulator piston
-Causes of internal leaks
-Causes of burned clutch plates
Does vehicle move?
NO
' Check for suspected conditions modifying delays to clutch apply:
-2nd clutch seal damaged
-Excessive 2nd clutch piston travel
-Defective accumulator piston
-Causes of internal leaks
-Check ball missing or out of
location in 2nd clutch
-Seals cut, damaged or missing
- Gaskets defective
-Causes of burned clutch plates Check
for suspected
conditions modifying delays to clutch apply:
-4th clutch seal damaged
-Excessive 4th clutch piston travel
-Defective 3-4 accumulator piston
-Causes of internal leaks
-Causes of burned clutch plates
* : Perform this test within safe and legal limits.
..

AUTOMATIC TRANSMISSION (4l30-E) 7 A-31
CHART 7: HARSH 1-2 SHIFT
PERFORM PRELIMINARY INSPECTION FIRST!
Normal line pressure
Check for 1-2 accumulator valve (320)
stuck by foreign material in main case valve body
Check line pressure (
Refer
to Line
Pressure chart) i" this Sectjgp.
High line pressure
Use
CHART 15b: POSSIBLE CAUSES
OF HIGH LINE PRESSURE eA 13119&.
~
CHART 8: HARSH 3-4 SHIFT
PERFORM PRELIMINARY INSPECTION FIRST!
Normal line pressure
Check for 3-4 accumulator valve (407) stuck in adapter case valve body (401)
Check for 3-4 accumulator piston (18)
stuck in adapter case (20)
( ) Refer to Parts List at the end of this Section.
line pressure (
Refer
to Line
Pressure chart) ..i.Ro tl,is Sectiou.
High line pressure
Use
CHART 15b: POSSIBLE CAUSES OF HIGH LINE PRESSURE on 1'88&­
~

7 A-32 AUTOMATIC TRANSMISSION (4L30-E)
CHART 9a: 3-2 DOWNSHIFT COMPLAINT
PERFORM PRELIMINARY INSPECTION FIRST!
Normal line pressure
Replace band apply solenoid (PWM)
(323)
Check line pressure
( ~efe~ to Lin_e Pressure chart)
·~!!.~n.
Low line pressure
Use
CHART 15a: POSSIBLE CAUSES OF LOW LINE PRESSURE EMil paae 74-37
CHART 9b: HARSH SHIFT WHEN SHIFTING INTO non OR ACCELERATING FROM STOP
PERFORM PRELIMINARY INSPECTION FIRST!
Normal line pressure
Replace band apply solenoid (PWM)
(323)
Check
line pressure (
Refer
to Line
Pressure chart) ifl.tAis Se&ti.cn.
High line pressure
Use
CHART 15b: POSSIBLE CAUSES OF
HIGH LINE PRESSURE eA Pille 1A 98
CHART 9c: COASTDOWN HARSH SHIFT OR CLUNK AT 3-2 DOWNSHIFT
PERFORM PRELIMINARY INSPECTION FIRST!
Normal line pressure
Replace band apply solenoid (PWM)
(323)
( ) Refer to Parts List at the end of this Section.
Check
line pressure (
Refer
to Line Pressure
chart) itt-thi& Seg~ian.
High line pressure
Use
CHART 15b: POSSIBLE CAUSES OF
HIGH LINE PRESSURE 011 page m:38

AUTOMATIC TRANSMISSION (4L30·E) 7 A-33
CHART 10: INTERMITTENT 4TH TO 2ND GEAR DOWNSHIFT AT. STEADY SPEED
PERFORM PRELIMINARY INSPECTION FIRST!
Check for consistent speed
sensor reading
with TECH1
Replace mode switch for intermittent
contact
1-------1 Check for wiring harness damage L...------1 or short to ground
OK
Check transmission speed sensor
connections
OK
Replace transmission speed
sensor