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SAT631IB
IntroductionNBAT0019
SAT632I
SEF234G
The TCM receives a signal from the vehicle speed sensor, throttle
position sensor or PNP switch and provides shift control or lock-up
control via A/T solenoid valves.
The TCM also communicates with the ECM by means of a signal
sent from sensing elements used with the OBD-related parts of the
A/T system for malfunction-diagnostic purposes. The TCM is
capable of diagnosing malfunctioning parts while the ECM can
store malfunctions in its memory.
Input and output signals must always be correct and stable in the
operation of the A/T system. The A/T system must be in good
operating condition and be free of valve seizure, solenoid valve
malfunction, etc.
It is much more difficult to diagnose a problem that occurs intermit-
tently rather than continuously. Most intermittent problems are
caused by poor electric connections or improper wiring. In this
case, careful checking of suspected circuits may help prevent the
replacement of good parts.
A visual check only may not find the cause of the problems. A road
test with CONSULT-II (or GST) or a circuit tester connected should
be performed. Follow the ªWork Flowº. Refer to AT-57.
Before undertaking actual checks, take a few minutes to talk with
a customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such problems, espe-
cially intermittent ones. Find out what symptoms are present and
under what conditions they occur. A ªDiagnostic Worksheetº like the
example (AT-55) should be used.
Start your diagnosis by looking for ªconventionalº problems first.
This will help troubleshoot driveability problems on an electronically
controlled engine vehicle.
Also check related Service bulletins.GI
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TROUBLE DIAGNOSIS Ð INTRODUCTION
Introduction
AT-53
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SAT496G
IBefore road test, familiarize yourself with all test procedures
and items to check.
IConduct tests on all items until specified symptom is found.
Troubleshoot items which check out No Good after road test.
Refer to ªON BOARD DIAGNOSTIC SYSTEM DESCRIP-
TIONº and ªTROUBLE DIAGNOSES FOR SYMPTOMSº,
AT-33 - AT-50 and AT-215 - AT-257.
1. CHECK BEFORE ENGINE IS STARTEDNBAT0024S02
1 CHECK O/D OFF INDICATOR LAMP
1. Park vehicle on flat surface.
2. Move selector lever to ªPº position.
3. Turn ignition switch to ªOFFº position.
Wait at least 5 seconds.
SAT967I
4. Turn ignition switch to ªONº position. (Do not start engine.)
5. Does O/D OFF indicator lamp come on for about 2 seconds?
SAT133K
YesorNo
Ye s©GO TO 2.
No©Go to ª1. O/D OFF Indicator Lamp Does Not Come Onº, AT-218.
TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Road Test (Cont'd)
AT-64
Page 189 of 2395
SAT132K
Component InspectionNBAT0205THROTTLE POSITION SWITCHNBAT0205S01Closed Throttle Position Switch (Idle position)NBAT0205S0101ICheck continuity between terminals 5 and 6.
[Refer to ªPreparationº, ªTCM SELF-DIAGNOSTIC PROCE-
DURE (No Tools)º, AT-46.]
Accelerator pedal condition Continuity
Released Yes
Depressed No
ITo adjust closed throttle position switch, refer to EC-154, ªSystem
Descriptionº.
SAT137K
Wide Open Throttle Position SwitchNBAT0205S0102ICheck continuity between terminals 4 and 5.
Accelerator pedal condition Continuity
Released No
Depressed Yes
DTC P1705 THROTTLE POSITION SENSOR
Component Inspection
AT-184
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Diagnostic ProcedureNBAT0230
1 CHECK CIRCUIT BETWEEN TCM AND ECM
1. Turn ignition switch to OFF position.
2. Check continuity between TCM terminal 33 and ECM terminal 114.
SAT640JA
OK or NG
OK©GO TO 2.
NG©Repair or replace harness and connector between TCM and ECM.
2 CHECK DTC WITH ECM STEP 1
Perform self-diagnosis for engine control. Refer to EC-74, ªDESCRIPTIONº.
OK or NG
OK©GO TO 4.
NG©GO TO 3.
3 CHECK DTC WITH ECM STEP 2
Check ECM. Refer to EC-440 and EC-603, ªSystem Descriptionº and ªComponent Descriptionº.
OK or NG
OK©GO TO 4.
NG©Repair or replace damaged parts.
4 CHECK DTC
Perform Diagnostic Trouble Code (DTC) confirmation procedure, AT-208.
OK or NG
OK©INSPECTION END
NG©GO TO 5.
5 CHECK TCM INSPECTION
If NG, recheck TCM pin terminals for damage or loose connection with harness connector.
OK or NG
OK©INSPECTION END
NG©Repair or replace damaged parts.
DTC A/T COMMUNICATION LINE
Diagnostic Procedure
AT-210
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2. Engine Cannot Be Started In ªPº and ªNº
Position
=NBAT0074SYMPTOM:
Engine cannot be started with selector lever in ªPº or ªNº
position.
Engine cannot be started with selector lever in ªPºEngine can
be started with selector lever in ªDº, ª2º, ª1º or ªRº position.
1 CHECK PNP SWITCH CIRCUIT
With CONSULT-II
Does ªTCM INPUT SIGNALSº in Data Monitor show damage to PNP switch circuit?
Without CONSULT-II
Does self-diagnosis show damage to PNP switch circuit?
SAT367J
YesorNo
Ye s©Check PNP switch circuit. Refer to ªDTC P0705º, AT-99.
No©GO TO 2.
2 CHECK PNP SWITCH INSPECTION
Check for short or open of PNP switch 2-pin connector. Refer to ªComponents Inspectionº, AT-103.
SAT838BB
OK or NG
OK©GO TO 3.
NG©Repair or replace PNP switch.
3 CHECK STARTING SYSTEM
Check starting system. Refer to SC-10, ªSystem Descriptionº.
OK or NG
OK©INSPECTION END
NG©Repair or replace damaged parts.
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TROUBLE DIAGNOSES FOR SYMPTOMS
2. Engine Cannot Be Started In ªPº and ªNº Position
AT-221
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SAT132K
Throttle Position SwitchNBAT0204S0403Closed Throttle Position Switch (Idle Position)
ICheck continuity between terminals 5 and 6.
[Refer to ªPreparationº, ªTCM SELF-DIAGNOSTIC PROCE-
DURE (No Tools)º, AT-46.]
Accelerator pedal condition Continuity
Released Yes
Depressed No
ITo adjust closed throttle position switch, refer to EC-431, ªSystem
Descriptionº.
SAT137K
Wide Open Throttle Position Switch
ICheck continuity between terminals 4 and 5.
Accelerator pedal condition Continuity
Released No
Depressed Yes
SAT251JA
A/T Fluid Temperature SwitchNBAT0204S04041. Make sure the A/T fluid warning lamp lights when the key is
inserted and turned to ªONº.
2. Make sure the A/T fluid warning lamp goes off when turning the
ignition switch to ªONº.
3. Check resistance between terminal 10 and ground while
changing temperature as shown at left.
Temperature ÉC (ÉF) Resistance
140 (284) or more Yes
140 (284) or less No
TROUBLE DIAGNOSES FOR SYMPTOMS
21. TCM Self-diagnosis Does Not Activate (PNP, Overdrive Control and Throttle Position Switches Circuit Checks) (Cont'd)
AT-264
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DescriptionNBAT0093IThe mechanical key interlock mechanism also operates as a
shift lock:
With the key switch turned to ªONº, the selector lever cannot
be shifted from ªPº (parking) to any other position unless the
brake pedal is depressed.
With the key removed, the selector lever cannot be shifted
from ªPº to any other position.
The key cannot be removed unless the selector lever is placed
in ªPº.
IThe shift lock and key interlock mechanisms are controlled by
the ON-OFF operation of the shift lock solenoid and by the
operation of the rotator and slider located inside the key
cylinder, respectively.
SAT145K
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A/T SHIFT LOCK SYSTEM
Description
AT-265
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Wiring Diagram Ð SHIFT ÐNBAT0094
MAT921A
A/T SHIFT LOCK SYSTEM
Wiring Diagram Ð SHIFT Ð
AT-266