AT-52
[EURO-OBD]
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
Diagnostic Procedure Without CONSULT-IIECS004QN
EURO-OBD SELF-DIAGNOSTIC PROCEDURE (WITH GST)
Refer to EC-112, "Generic Scan Tool (GST) Function" (WITH EURO-OBD).
EURO-OBD SELF-DIAGNOSTIC PROCEDURE (NO TOOLS)
Refer toEC-64, "Malfunction Indicator (MI)" (WITH EURO-OBD) or EC-516, "Malfunction Indicator (MI)"
(WITHOUT EURO-OBD).
TCM SELF-DIAGNOSTIC PROCEDURE (NO TOOLS)
1. CHECK O/D OFF INDICATOR LAMP
1. Selector lever in P position.
2. Turn ignition switch to OFF position.
3. Wait 5 seconds.
4. Set overdrive control switch to ON position.
5. Turn ignition switch to ON position. (Do not start engine.)
Does O/D OFF indicator lamp come on for about 2 seconds?
YES >> GO TO 2.
NO >> Go to AT- 2 0 4 , "
O/D OFF Indicator Lamp Does Not
Come On" .
2. JUDGEMENT PROCEDURE STEP 1
1. Turn ignition switch to OFF position.
2. Move selector lever to D position.
3. Set overdrive control switch to OFF position.
4. Turn ignition switch to ON position. (Do not start engine.)
–Wait more than 2 seconds after turning ignition switch ON.
>> GO TO 3.
SAT774B
SCIA5468E
SAT653E
TROUBLE DIAGNOSIS — INTRODUCTION
AT-57
[EURO-OBD]
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TROUBLE DIAGNOSIS — INTRODUCTIONPFP:00000
IntroductionECS004QO
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 EURO-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 oper-
ating condition and be free of valve seizure, solenoid valve malfunc-
tion, 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 replace-
ment 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 “Work Flow”. Refer to AT- 6 1 , "
Work Flow" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a drive ability complaint. The cus-
tomer can supply good information about such problems, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A “Diagnostic Worksheet” like the exam-
ple (AT- 5 8 , "
DIAGNOSTIC WORKSHEET" ) should be used.
Start your diagnosis by looking for “conventional” problems first. This
will help troubleshoot drive ability problems on an electronically con-
trolled engine vehicle.
Also check related Service bulletins for information.
SAT631IA
SAT632I
SEF234G
TROUBLE DIAGNOSIS — INTRODUCTION
AT-59
[EURO-OBD]
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Diagnostic Worksheet
1.❏ Read the Fail-safe and listen to customer complaints.AT- 5 8
2.❏ Check A/T fluidAT- 6 4
❏ Leakage (Follow specified procedure)
❏ Fluid condition
❏ Fluid level
3.❏ Perform Stall Test and Line Pressure Test.AT- 6 5
, AT- 6 8
❏ Stall test — Mark possible damaged components/others.
❏ Torque converter one-way clutch
❏ Reverse clutch
❏ Forward clutch
❏ Overrun clutch
❏ Forward one-way clutch❏ Low & reverse brake
❏ Low one-way clutch
❏ Engine
❏ Line pressure is low
❏ Clutches and brakes except high clutch and
brake band are OK
❏ Line Pressure test — Suspected parts:
4.❏ Perform all Road Test and mark required procedures.AT- 7 0
4-1. Check before engine is started.AT- 7 1
❏ O/D OFF Indicator Lamp Does Not Come On, AT-204 .
❏ SELF-DIAGNOSTIC PROCEDURE/DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION PRO-
CEDURE. — Mark detected items.
❏ PNP switch, AT- 1 0 0
.
❏ A/T fluid temperature sensor, AT- 1 0 6
.
❏ Vehicle speed sensor·A/T (Revolution sensor), AT- 11 2
.
❏ Engine speed signal, AT- 11 9
.
❏ Torque converter clutch solenoid valve, AT-148
.
❏ Line pressure solenoid valve, AT-154
.
❏ Shift solenoid valve A, AT- 1 6 1
.
❏ Shift solenoid valve B, AT- 1 6 7
.
❏ Accelerator pedal position (App) sensor, AT- 1 7 3
.
❏ Overrun clutch solenoid valve, AT- 1 7 8
.
❏ PNP & overdrive control switches, and throttle position sensor, AT- 2 3 7
.
❏ Batt/fluid temp sen (A/T fluid temperature sensor and TCM power source), AT- 1 8 4
.
❏ Vehicle speed sensor·MTR, AT-192
.
❏ CAN communication line, AT- 9 7
.
❏ Control unit (RAM), control unit (ROM), AT-198
.
❏ Control unit (EEP ROM), AT-200
.
❏ Battery
❏ Others
4-2. Check at idleAT- 7 2
❏ Engine Cannot Be Started In “P” And “N” Position, AT-206 .
❏ In “P” Position, Vehicle Moves Forward Or Backward When Pushed, AT-207
.
❏ In “N” Position, Vehicle Moves, AT- 2 0 8
.
❏ Large Shock. “N” → “R” Position, AT-209
.
❏ Vehicle Does Not Creep Backward In “R” Position, AT-210
.
❏ Vehicle Does Not Creep Forward In “D”, “2” Or “1” Position, AT- 2 1 2
.
AT-60
[EURO-OBD]
TROUBLE DIAGNOSIS — INTRODUCTION
4. 4-3. Cruise testAT- 7 4
AT- 7 8Part-1
❏ Vehicle Cannot Be Started From D
1 , AT-214 .
❏ A/T Does Not Shift: D
1 → D2 Or Does Not Kickdown: D4 → D2 , AT- 2 1 7 .
❏ A/T Does Not Shift: D
2 → D3 , AT-220 .
❏ A/T Does Not Shift: D
3 → D4 , AT-222 .
❏ A/T Does Not Perform Lock-up, AT- 2 2 4
.
❏ A/T Does Not Hold Lock-up Condition, AT- 2 2 5
.
❏ Lock-up Is Not Released, AT- 2 2 7
.
❏ Engine Speed Does Not Return To Idle (Light Braking D
4 → D3 ), AT- 2 2 8 .
Part-2AT- 8 1
❏ Vehicle Does Not Start From D1 , AT-230 .
❏ A/T Does Not Shift: D
1 → D2 Or Does Not Kickdown: D4 → D2 , AT- 2 1 7 .
❏ A/T Does Not Shift: D
2 → D3 , AT-220 .
❏ A/T Does Not Shift: D
3 → D4 , AT-222 .
Part-3AT- 8 2
❏ A/T Does Not Shift: D4 → D3 When Overdrive Control Switch “ON” → “OFF”, AT- 2 3 1 .
❏ Engine Speed Does Not Return To Idle (Engine Brake In D
3 ), AT-228 .
❏ A/T Does Not Shift: D
3 → 22 , When Selector Lever “D” → “2” Position, AT-232 .
❏ Engine Speed Does Not Return To Idle (Engine Brake In 2
2 ), AT- 2 2 8 .
❏ A/T Does Not Shift: 2
2 → 11 , When Selector Lever “2” → “1” Position, AT- 2 3 3 .
❏ Vehicle Does Not Decelerate By Engine Brake, AT-235
.
❏ TCM Self-diagnosis Does Not Activate (PNP & Overdrive control switches, and throttle position sensor
circuit checks), AT-237
.
❏ SELF-DIAGNOSTIC PROCEDURE/DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION PRO-
CEDURE — Mark detected items.
❏ PNP switch, AT-100
.
❏ A/T fluid temperature sensor, AT-106
.
❏ Vehicle speed sensor·A/T (Revolution sensor), AT- 11 2
.
❏ Engine speed signal, AT- 11 9
.
❏ Torque converter clutch solenoid valve, AT- 1 4 8
.
❏ Line pressure solenoid valve, AT-154
.
❏ Shift solenoid valve A, AT-161
.
❏ Shift solenoid valve B, AT-167
.
❏ Accelerator pedal position (App) sensor, AT-173
.
❏ Overrun clutch solenoid valve, AT-178
.
❏ PNP & overdrive control switches, and throttle position sensor, AT- 2 3 7
.
❏ A/T fluid temperature sensor and TCM power source, AT-184
.
❏ Vehicle speed sensor·MTR, AT- 1 9 2
.
❏ CAN communication line, AT- 9 7
.
❏ Control unit (RAM), control unit (ROM), AT- 1 9 8
.
❏ Control unit (EEP ROM), AT- 2 0 0
.
❏ Battery
❏ Others
5.❏ For self-diagnosis NG items, inspect each component. Repair or replace the damaged parts.AT- 5 2
6.❏ Perform all Road Test and re-mark required procedures.AT- 7 0
7.❏ Perform DTC Confirmation Procedure for following MILL indicating items and check out NG items.EC-52
❏ DTC (P0731) A/T 1st gear function, AT-125 .
❏ DTC (P0732) A/T 2nd gear function, AT- 1 3 0
.
❏ DTC (P0733) A/T 3rd gear function, AT-135
.
❏ DTC (P0734) A/T 4th gear function, AT-140
.
8.❏ Perform the Diagnostic Procedures for all remaining items marked NG. Repair or replace the damaged parts.
Refer to the Symptom Chart when you perform the procedures. (The chart also shows some other possible
symptoms and the component inspection orders.)AT- 8 5
9.❏ Erase DTC from TCM and ECM memories.AT- 4 2
AT-64
[EURO-OBD]
TROUBLE DIAGNOSIS — BASIC INSPECTION
TROUBLE DIAGNOSIS — BASIC INSPECTIONPFP:00000
A/T Fluid CheckECS004QQ
FLUID LEAKAGE CHECK
1. Clean area suspected of leaking. — for example, mating surface
of converter housing and transmission case.
2. Start engine, apply foot brake, place selector lever in D position
and wait a few minutes.
3. Stop engine.
4. Check for fresh leakage.
FLUID CONDITION CHECK
FLUID LEVEL CHECK
Refer to AT- 1 6 , "Checking A/T Fluid" .
SAT767B
SAT288G
Fluid color Suspected problem
Dark or black with burned odor Wear of frictional material
Milky pink Water contamination — Road water
entering through filler tube or breather
Varnished fluid, light to dark brown and
tackyOxidation — Over or under filling, —
Overheating
SAT638A
TROUBLE DIAGNOSIS — BASIC INSPECTION
AT-65
[EURO-OBD]
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Stall TestECS004QR
STALL TEST PROCEDURE
1. Check A/T fluid and engine oil levels. If necessary, add.
2. Drive vehicle for approx. 10 minutes or until fluid and oil reach
operating temperature. Refer to AT- 1 6 , "
Checking A/T Fluid" .
3. Set parking brake and block wheels.
4. Install a tachometer where it can be seen by driver during test.
It is good practice to mark the point of specified engine
rpm on indicator.
5. Start engine, apply foot brake, and place selector lever in D
position.
6. Accelerate to wide open throttle gradually while applying foot
brake.
7. Quickly note the engine stall revolution and immediately release
throttle.
During test, never hold throttle wide open for more than 5
seconds.
SAT647B
SAT513G
SAT775B
Stall revolution:
QR20DE: 2,450 - 2,950 rpm
QR25DE: 2,300 - 2,750 rpm
SAT514G
AT-66
[EURO-OBD]
TROUBLE DIAGNOSIS — BASIC INSPECTION
8. Move selector lever to N position.
9. Cool off ATF.
Run engine at idle for at least one minute.
10. Repeat steps 5 through 9 with selector lever in 2, 1 and R posi-
tions.
JUDGEMENT OF STALL TEST
The test result and possible damaged components relating to each result are shown in the illustrations on next
page.
In order to pinpoint the possible damaged components, follow the WORK FLOW shown in AT- 6 1 , "
Work Flow"
(EURO-OBD).
NOTE:
Stall revolution is too high in D, 2 or 1 position:
Slippage occurs in 1st gear but not in 2nd and 3rd gears...... Low one-way clutch slippage
Slippage occurs in the following gears:
1st through 3rd gears in D position and engine brake functions with overdrive control switch set to OFF.
1st and 2nd gears in 2 position and engine brake functions with accelerator pedal released (fully closed
throttle)...... Forward clutch or forward one-way clutch slippage
Stall revolution is too high in R position:
Engine brake does not function in 1 position...... Low & reverse brake slippage
Engine brake functions in 1 position...... Reverse clutch slippage
Stall revolution within specifications:
Vehicle does not achieve speed of more than 80 km/h (50 MPH)...... One-way clutch seizure in torque
converter housing
CAUTION:
Be careful since automatic fluid temperature increases abnormally.
Slippage occurs in 3rd and 4th gears in D position...... High clutch slippage
Slippage occurs in 2nd and 4th gear in D position...... Brake band slippage
Engine brake does not function in 2nd and 3rd gears in D position, 2nd gear in 2 position, and 1st gear in
1 position with overdrive control switch set to OFF...... Overrun clutch slippage
Stall revolution less than specifications:
Poor acceleration during starts...... One-way clutch slippage in torque converter
SAT771B
TROUBLE DIAGNOSIS — BASIC INSPECTION
AT-69
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5. Start engine and measure line pressure at idle and stall speed.
When measuring line pressure at stall speed, follow the
stall test procedure.
LINE PRESSURE
JUDGEMENT OF LINE PRESSURE TEST
SAT493G
Check lock-up hold.Line pressure kPa (bar, kg/cm2 , psi)
“D”, “2” and “1” positions “R” position
Idle 500 (5.00, 5.1, 73) 778 (7.78, 7.9, 113)
Stall 1,233 (12.33, 12.6, 179) 1,918 (19.18, 19.6, 278)
Judgement Suspected parts
At idleLine pressure is low in all positions.
Oil pump wear
Control piston damage
Pressure regulator valve or plug sticking
Spring for pressure regulator valve damaged
Fluid pressure leakage between oil strainer and pressure regulator valve
Clogged strainer
Line pressure is low in particular posi-
tion.
Fluid pressure leakage between manual valve and particular clutch
For example, line pressure is:
− Low in “R” and “1” positions, but
− Normal in “D” and “2” positions.
Therefore, fluid leakage exists at or around low and reverse brake circuit.
Refer to AT- 2 3
.
Line pressure is high.
Maladjustment of throttle position sensor
A/T fluid temperature sensor damaged
Line pressure solenoid valve sticking
Short circuit of line pressure solenoid valve circuit
Pressure modifier valve sticking
Pressure regulator valve or plug sticking
Open in dropping resistor circuit
At stall
speedLine pressure is low.
Maladjustment of throttle position sensor
Line pressure solenoid valve sticking
Short circuit of line pressure solenoid valve circuit
Pressure regulator valve or plug sticking
Pressure modifier valve sticking
Pilot valve sticking