1995 ISUZU TROOPER Workshop Manual

AUTOMATIC TRANSMISSION (4L30-E) 7 A-121
DIAGNOSTIC TROUBLE CODE (DTC) 51
ENGINE COOLANT SWITCH SHORT TO GROUND, PLUS OR OPEN
• This DTC can be set when there is no problem at
all. This is due to the fact that when the engine
stalls the ignition is still ON then Engine Control
Module (ECM) provides a false information:
engine cold. The Transmission Control Module
(TCM), knowing that the last ignition cycle
happened more than 20 minutes ago, then sets
DTC51.
• Check voltage between connector C-91 terminal 014 and connector C-91 terminal C1 (TCM ground). • Ignition switch ON. Engine ON. Engine warm. IF: Voltage higher than 5 volts:
•
There is a short circuit to voltage.
•
Repair.
• Using the Scan Tool you can check with TECH1:
FO: ENG. TEMP. SW information. When the
engine is
cold or when the engine is OFF the
TECH1 should show: COLD. When the engine is
warm the TECH1 should show WARM.
• This DTC is not very important. In the worst case
it would not allow the Torque Converter Clutch
(TCC) to be applied. This will cause low fuel
economy.
There is not currently a problem. GOTO INTERMITTENT CONDITIONS.
• This is an open circuit or the ECM is not sending the correct information. See also ECM information, SeetiQR 6E.
• Voltage approx. 0 volts means that the signal is OK or that
there is a short circuit to ground. • Repair.
There is
not currently a problem. GOTO INTERMITTENT CONDITIONS.
• Turn the engine OFF with the ignition ON. IF: The voltage goes back to 5
volts:
•
As the voltage is staying at 0 volts, there is a short to ground. • Repair.

7A-122 AUTOMATIC TRANSMISSION (4L30-E)
DIAGNOSTIC TROUBLE CODE (DTC) 52
KICK DOWN ALWAYS ON OR SHORT TO GROUND
This DTC does NOT flash the CHECK TRANS
indicator and does
NOT set the BACKUP MODE.
Circuit Description:
• When the driver presses the accelerator pedal
down fully, the kick down switch closes, sending
a
ground signal to the Transmission Control
Module (TCM).
• This information is used to do shifts with a high
Engine Speed RPM.
• When the kick down switch is closed the Throttle
Position Sensor (TPS) is already at 100%.
Diagnostic Aids:
• This diagnostic is not an electrical test done by
the TCM but a test between different information
("logic test").
1
I
I
I
I
----
KICK DOWN SWITCH INPtit
C-90 LT BLU
85
C-91 H-11
• Detection conditions:
G) Kick down switch ON (short to ground) and
TPS
<70%.
@ No malfunction: TPS short to voltage or
ground (DTC21 and DTC22).
@ The conditions need to be present for at least
1 second.
•
Action after the detection time: Kick Down
information not taken into account.
• Recovery conditions: To recover, Kick Down
needs
to be seen as OFF during detection time.
H-7
'}-1 KICK DOWN I SWITCH
I { I ? BLKJORN ~
I GROUND II C1 BLKJBLU :q ) D1 < I ____ , 1
TRANSMISSION
I
l~··j1
1 r::o
CONTROL
MODULE ITCM)
•

AUTOMATIC TRANSMISSION (4L30-E) 7A-123
DIAGNOSTIC TROUBLE CODE (DTC) 52
KICK DOWN ALWAYS ON OR SHORT TO GROUND
IF: DTC 23 Throttle Position Sensor (TPS) connector
• Ignition switch ON. Engine OFF.
• Accelerator pedal not depressed. • Connect a voltmeter between connector C-90
terminal B5 and connector C-91 terminal C1 (TCM
ground).
IF: Display approx. 0 volts:
•
Check the wires and connector
and the switch to detect the
short to ground.
• Repair. The
problem is
intermittent. GOTO INTERMITTENT
CONDITIONS.

7A-124 AUTOMATIC TRANSMISSION (4L30-E)
DIAGNOSTIC TROUBLE CODE (DTC) 53
MODE SWITCH IN P OR N OR R BAD POSITION
This DTC does NOT flash the CHECK TRANS
indicator and does NOT set the BACKUP MODE.
Circuit Description:
• The mode switch supplies the Transmission
Control Module (TCM) with information regard­
ing
the selector lever position: P, R, N, D, 3, 2 or
L. The selector lever position is indicated by the
state
of four ON/OFF contacts. The mode switch
is located on one side of the transmission. It is
on
the transmission manual shaft and is fixed to
the main case.
• The mode switch is also used to provide the
information P or N to the engine crank wiring.
The engine can be cranked only if connector C-43
terminal 4(H) is connected to terminal 1(E), which
is connected to ground.
• The mode switch is also used to provide the back
up lamp power in reverse. This is the reason
why the mode switch is supplied through a 15A
fuse
(C-3). This fuse can burn due to short circuit
in the back up lamp.
•
When this fuse is open, the mode switch does
not work and DTC54 is set.
• The mode position is defined by the shift linkage
which is a link between the shift lever and the
mode switch. A bad adjustment of the shift link­
age can create a mode switch problem (DTC53).
Diagnostic Aids:
• This Diagnostic is not an electrical test done by
the TCM but a test between different information
("logic test").
•
Detection conditions of P or N bad position:
CD A/T Input Speed <3000 RPM
0 TPS > 20%
@ Mode Switch = P or N
® No malfunction: TPS short to voltage or
ground (DTC21, DTC22), Engine Speed
(DTC13).
® The conditions need to be present for at least
4 seconds.
• Action after the detection time: Default position
assumed for pressure calculation and shift
pattern =always in D.
• Recovery Conditions: To recover, have the
engine speed higher than 3000 RPM with a TPS
higher than 20% when the mode switch is not in
PorN.
• Detection conditions of R bad position:
CD A/T Output Speed> approx. 100 KPH
0 Mode Switch= R
@ No malfunction: Output speed (DTC11).
Downshift Protection (DTC62).
® The conditions need to be present for at least
4 seconds.
• Action aft,:H the detection time: Default position
assumed for pressure calculation and shift
pattern = always in D.
• Recovery conditions: To recover, have the output
speed hi~1her than 100 KPH when the mode
switch is not R.
'''·"'·'lllfHJi'.!d'
1
-FUSe C-3 --~ FUSE BOX 16A I I STARTER RELAY
L _____ l I
~~J~Jr'~~~ION RED/BLK BLU/RED
I "'R 2 I R 2J 'R 2 • R 2J I
I '1o N D 3 ~/ l' N D 3 '( D ; / I
:~1-_-_-_~:-~ ~ ~'~t ~-: ~"~\_-_-~-_!!;~= = = ==~-: 2(F) "[ 6(C) 7(B) BIA) 3(G) liE) "'I C-43
BACKUP ( RED/BLU. . BLU ~It
LAMP ~'"""" "'""" "' e> < INPUT RELAY I MODULE
B4 '-- - -_Q6 - - - -_27 '-- - -_Q4 C-91 4 ~ - - -_co~T~L J
r - - - - - - - - - - - - - - - - - --- -- -1 TRANsM1ss1oN
I ~~~0RL~LITCM) I TRANSMISSION CONTROL INPUTS I
~-----------------------~
•

AUTOMATIC TRANSMISSION (4l30-E) 7 A-125
DIAGNOSTIC TROUBLE CODE (DTC) 53
MODE SWITCH IN P OR N OR R BAD POSITION
IF: DTC 23 Throttle Position Sensor (TPS) connector
open or DTC 13 Engine speed, DTC 54 Mode switch
illegal position exists:
Table 1
TECH1 DISPLAY p
SELECTOR PIN A X
SELECTOR PIN B
SELECTOR PIN C
SELECTOR PIN P X
• Install scan tool GOTHROUGH TECH1 CONNECTION.
• Ignition switch ON. Engine running.
• Selector lever position "P". • Select FO: DATALIST: "TOP SIGNAL" or FO: DATA LIST: "AT INPUT SPEED".
IF: Display does not change with engine speed or TPS:
DTC 23 or DTC 13 not detected
but are the reason for this DTC 53.
GOTO DTC13 or DTC23.
R
X
X
The problem is
intermittent. GOTO
INTERMITTENT
CONDITIONS.
SHIFT
SELECTOR POSITION
N D
3
X
X X X
X
X
X X
2 L
X
X X
X
• Ignition switch ON.
• Select FO: DATALIST: "SELECTOR POS.".
• Move shift selector lever through all positions
and compare
results with table 1. IF: all selector pin displays correct:
• Check automatic transmission mode switch
adjustment. GOTHROUGH MODE SWITCH
SETTING PROCEDURE (~. ;"A•1~'Yl
• Repair.
Note:
"X" indicatesTECH1 displays "ACTIVE".