DIAGNOSTIC PROCEDURE
CHECK GROUND CIRCUIT.
1. Turn ignition switch to ªOFFº position.
2. Disconnect terminal cord assembly
connector in engine compartment.
3. Check resistance between terminalq
4
and ground.
Resistance: 2.5 - 5W
OK
ENG
1. Remove control valve
assembly. Refer to
AT-113.
2. Check the following
items:
ILine pressure solenoid
valve
Refer to ªCOMPO-
NENT INSPECTIONº
on next page.
IHarness of terminal
cord assembly for
short or open
CHECK POWER SOURCE CIRCUIT.
1. Turn ignition switch to ªOFFº position.
2. Disconnect TCM harness connector.
3. Check resistance between terminalq
4
and TCM harness connector terminal
q
2.
Resistance: 11.2 - 12.8W
OK
ENG
Check the following items:
IDropping resistor
Refer to ªCOMPONENT
INSPECTIONº on next
page.
IHarness for short or
open between TCM ter-
minalq
2and terminal
cord assembly (Main
harness)
CHECK POWER SOURCE CIRCUIT.
1. Turn ignition switch to ªOFFº position.
2. Check resistance between terminalq
6
and TCM harness connector terminal
q
1.
Resistance:
Approximately 0W
If OK, check harness for short to
ground and short to power.
3. Reinstall any part removed.
OK
ENG
Repair open circuit or short
to ground or short to
power in harness or con-
nector.
Perform ªSELF-DIAGNOSIS CODE CON-
FIRMATION PROCEDUREº, AT-84.
OK
ENG
1. Perform TCM input/
output signal inspection.
2. If NG, recheck TCM pin
terminals for damage or
loose connection with
harness connector.
INSPECTION END
YAT321
YAT322
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TROUBLE DIAGNOSIS FOR LINE PRESSURE S/V
Line Pressure Solenoid Valve (Cont'd)
AT-85
DIAGNOSTIC PROCEDURE
CHECK PARK/NEUTRAL POSITION
SWITCH CIRCUIT.
1. Turn ignition switch to ªONº posi-
tion.
(Do not start engine.)
2. Select ªECU INPUT SIGNALSº in
Data Monitor.
3. Read out ªR, N, D, 2 and 1 posi-
tion switchesº moving selector
lever to each position.
Check the signal of the selector
lever position is indicated properly.
-----------------------------------------------------------------------------------------------------------------------OR -----------------------------------------------------------------------------------------------------------------------
1. Turn ignition switch to ªONº posi-
tion. (Do not start engine.)
2. Check voltage between TCM ter-
minalsq
26,q27,q34,q35,q36and
ground while moving selector
lever through each position.
Voltage:
B: Battery voltage
0: 0V
OK
ENG
Check the following items:
IPark/neutral position
switch
Refer to ªCOMPONENT
INSPECTIONº, AT-114.
IHarness for short or
open between ignition
switch and park/neutral
position switch (Main
harness)
IHarness for short or
open between park/
neutral position switch
and TCM (Main harness)
IDiode
qA
(Go to next page.)
Lever positionTerminal No.
q36q35q34q27q26
P, NB0000
R0B000
D00B00
2 000B0
1 0000B
YAT326
H
TROUBLE DIAGNOSIS FOR NON-DETECTABLE ITEMS
Park/neutral Position, Overdrive Control or
Throttle (Accelerator) Position Switches
(Cont'd)
AT-89
qA
CHECK OVERDRIVE CONTROL
SWITCH CIRCUIT.
1. Turn ignition switch to ªONº posi-
tion.
(Do not start engine.)
2. Select ªECU INPUT SIGNALSº in
Data Monitor.
3. Read out ªOVERDRIVE SWITCHº.
Check the signal of the overdrive
control switch is indicated prop-
erly.
(Overdrive control switch ªONº
displayed on CONSULT-II means
overdrive ªOFFº.)
-----------------------------------------------------------------------------------------------------------------------OR -----------------------------------------------------------------------------------------------------------------------
1. Turn ignition switch to ªONº posi-
tion.
(Do not start engine.)
2. Check voltage between TCM ter-
minalq
22and ground when over-
drive control switch is ªONº and
ªOFFº.
OK
ENG
Check the following items.
IOverdrive control switch
Refer to ªCOMPONENT
INSPECTIONº, AT-114.
IHarness for short or
open between TCM and
overdrive control switch
(Main harness)
IHarness for short or
open of ground circuit for
overdrive control switch
(Main harness)
qB(Go to next page.)
Switch position Voltage
ON Battery voltage
OFF 1V or less
YAT327
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TROUBLE DIAGNOSIS FOR NON-DETECTABLE ITEMS
Park/neutral Position, Overdrive Control or
Throttle (Accelerator) Position Switches
(Cont'd)
AT-90
qB
CHECK THROTTLE (ACCELERATOR)
POSITION SWITCH CIRCUIT.
1. Turn ignition switch to ªONº posi-
tion.
(Do not start engine.)
2. Select ªECU INPUT SIGNALSº in
Data Monitor.
3. Read out ªCLOSED THL/SWº and
ªW/O THRL/P-SWº depressing
and releasing accelerator pedal.
Check the signal of throttle (accel-
erator) position switch is indicated
properly.
-----------------------------------------------------------------------------------------------------------------------OR -----------------------------------------------------------------------------------------------------------------------
1. Turn ignition switch to ªONº posi-
tion.
(Do not start engine.)
2. Check voltage between TCM ter-
minalsq
16,q17and ground while
depressing, and releasing accel-
erator pedal slowly. (after warming
up engine)
OK
ENG
Check the following items:
IThrottle (accelerator)
position switch
Refer to ªCOMPONENT
INSPECTIONº, AT-114.
IHarness for short or
open between ignition
switch and throttle
(accelerator) position
switch (Main harness)
IHarness for short or
open between throttle
(accelerator) position
switch and TCM (Main
harness)
Perform ªDIAGNOSTIC PROCEDUREº,
AT-89.
OK
ENG
1. Perform TCM input/
output signal inspection.
2. If NG, recheck TCM pin
terminals for damage or
loose connection with
harness connector.
INSPECTION END
Accelerator
pedal condi-
tionData monitor
CLOSED
THL/SWW/O THRL/
P-SW
Released ON OFF
Fully
depressedOFF ON
Accelerator
pedal
conditionVoltage
Terminal
No.q
16Terminal No.
q17
ReleasedBattery
voltage1V or less
Fully
depressed1V or lessBattery
voltage
YAT328
YAT329
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TROUBLE DIAGNOSIS FOR NON-DETECTABLE ITEMS
Park/neutral Position, Overdrive Control or
Throttle (Accelerator) Position Switches
(Cont'd)
AT-91
1. SPORT Indicator Lamp Does Not Come On
SYMPTOM:
POWER indicator lamp does not come on for about 2 seconds
when turning ignition switch to ªONº.
CHECK TCM POWER SOURCE.
1. Turn ignition switch to ªONº position.
(Do not start engine.)
2. Check voltage between TCM terminals
q
4,q9and ground.
Battery voltage should exist.
OK
ENG
Check the following items:
IHarness for short or
open between ignition
switch and TCM (Main
harness)
IIgnition switch and fuse
Refer to EL section
(ªPOWER SUPPLY
ROUTINGº).
CHECK TCM GROUND CIRCUIT.
1. Turn ignition switch to ªOFFº position.
2. Disconnect TCM harness connector.
3. Check resistance between TCM termi-
nalsq
15,q48and ground.
Resistance:
Approximately 0W
If OK, check harness for short to
ground and short to power.
OK
ENG
Repair open circuit or short
to ground or short to
power in harness or con-
nector.
CHECK LAMP CIRCUIT.
1. Turn ignition switch to ªONº position.
2. Set overdrive control, A/T check or
power switch to ªONº position.
3. Check voltage between TCM terminal
q
39and ground.
Voltage: Battery voltage
4. Reinstall any part removed.
OK
ENG
Check the following items:
IFuse (7.5A)
ISPORT indicator lamp
Refer to EL section
(ªWARNING LAMPSº).
IHarness for short or
open between ignition
switch and SPORT indi-
cator lamp (Main har-
ness)
Refer to EL section
(ªPOWER SUPPLY
ROUTINGº).
IHarness for short or
open between SPORT
indicator lamp and TCM
Check again.
OK
ENG
1. Perform TCM input/
output signal inspection.
2. If NG, recheck TCM pin
terminals for damage or
loose connection with
harness connector.
INSPECTION END
YAT332
YAT333
YAT334
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DIAGNOSTIC PROCEDURES FOR SYMPTOMS
AT-94
5. Engine Cannot Be Started In ªPº and ªNº
Position
SYMPTOM:
IEngine cannot be started with selector lever in ªPº or ªNº
position.
IEngine can be started with selector lever in ªDº, ª2º, ª1º
or ªRº position.
Does ªECU INPUT SIGNALSº in
Data Monitor show damage to park/
neutral position switch circuit?
-----------------------------------------------------------------------------------------------------------------------OR -----------------------------------------------------------------------------------------------------------------------
Does self-diagnosis show damage to
park/neutral position switch circuit?
No
EYe s
Check park/neutral position
switch. Refer to AT-88.
Check for short or open of park/neutral
position switch 2-pin connector. Refer to
AT-88.
OK
ENG
Repair or replace park/
neutral position switch.
Check starting system. Refer to EL sec-
tion (ªSystem Descriptionº, ªSTARTING
SYSTEMº).
OK
ENG
Repair or replace dam-
aged parts.
INSPECTION END
6. In ªPº Position, Vehicle Moves Forward Or
Backward When Pushed
SYMPTOM:
Vehicle moves when it is pushed forward or backward with
selector lever in ªPº position.
Check parking pawl components. Refer to
AT-175.
OK
ENG
Repair or replace dam-
aged parts.
INSPECTION END
SAT146BA
NAT275
SAT133B
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DIAGNOSTIC PROCEDURES FOR SYMPTOMS
AT-97
16. A/T Does Not Hold Lock-up Condition
SYMPTOM:
A/T does not hold lock-up condition for more than 36 seconds.
Does self-diagnosis show damage to
engine speed signal circuit after cruise
test?
No
EYe s
Check engine speed sig-
nal. Refer to AT-80.
1. Remove oil pan.
2. Check A/T fluid condition.
OK
ENG
1. Remove control valve
assembly. Refer to
AT-113.
2. Check the following
items:
ITorque converter clutch
control valve
IPilot valve
IPilot filter
3. Disassemble A/T.
4. Check torque converter
and oil pump assembly.
1. Remove control valve assembly. Refer
to AT-113.
2. Check the following items:
ITorque converter clutch control valve
IPilot valve
IPilot filter
OKFOK
Check again.
OK
ENG
1. Perform TCM input/
output signal inspection.
2. If NG, recheck TCM pin
terminals for damage or
loose connection with
harness connector.
INSPECTION END
17. Lock-up Is Not Released
SYMPTOM:
Lock-up is not released when accelerator pedal is released.
Does ªECU INPUT SIGNALSº in
Data Monitor show damage to closed
throttle position switch circuit?
-----------------------------------------------------------------------------------------------------------------------OR -----------------------------------------------------------------------------------------------------------------------
Does self-diagnosis show damage to
closed throttle position switch circuit?
No
EYe s
Check closed throttle posi-
tion switch. Refer to AT-88.
Check again.
OK
ENG
1. Perform TCM input/
output signal inspection.
2. If NG, recheck TCM pin
terminals for damage or
loose connection with
harness connector.
INSPECTION END
SAT835H
SAT171B
SAT146BA
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DIAGNOSTIC PROCEDURES FOR SYMPTOMS
AT-107
18. Engine Speed Does Not Return To Idle
(Light Braking D
4®D3)
SYMPTOM:
IEngine speed does not smoothly return to idle when A/T
shifts from D
4to D3.
IVehicle does not decelerate by engine brake when turning
overdrive control switch OFF.
IVehicle does not decelerate by engine brake when shifting
A/T from ªDº to ª2º position.
Does self-diagnosis show damage to
overrun clutch solenoid valve circuit after
cruise test?
No
EYe s
Check overrun clutch sole-
noid valve. Refer to AT-69.
Check throttle (accelerator) position sen-
sor. Refer to EC section [TROUBLE
DIAGNOSIS FOR ªTHROTTLE (ACCEL)
POSI SENº].
OK
ENG
Repair or replace throttle
(accelerator) position sen-
sor.
1. Remove oil pan.
2. Check A/T fluid condition.
OK
ENG
1. Remove control valve
assembly. Refer to
AT-113.
2. Check the following
items:
IOverrun clutch control
valve
IOverrun clutch reducing
valve
IOverrun clutch solenoid
valve
3. Disassemble A/T.
4. Check the following
items:
IOverrun clutch assembly
IOil pump assembly
1. Remove control valve assembly. Refer
to AT-113.
2. Check the following items:
IOverrun clutch control valve
IOverrun clutch reducing valve
IOverrun clutch solenoid valve
OK
FOK
Check again.
OK
ENG
1. Perform TCM input/
output signal inspection.
2. If NG, recheck TCM pin
terminals for damage or
loose connection with
harness connector.
INSPECTION END
YAT338
NAT262
SAT171B
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DIAGNOSTIC PROCEDURES FOR SYMPTOMS
AT-108