AT-50
TROUBLE DIAGNOSIS
Cruise Test — Part 1BCS00106
1. CHECK STARTING GEAR (D1 ) POSITION
1. Drive vehicle for approximately 10 minutes to warm engine oil and ATF up to operating temperature.
2. Park vehicle on flat surface.
3. Move selector lever to “P” position.
4. Start engine.
5. Move selector lever to “D” position.
6. Accelerate vehicle by constantly depressing accelerator pedal half-way.
Read gear position. Refer to AT- 7 0 , "
DATA MONITOR MODE" .
Does vehicle start from D
1 ?
YES >> GO TO 2.
NO >>
Mark the box AT- 1 8 2 , "Vehicle Cannot Be Started From D1" on the AT- 3 8 , "DIAGNOSTIC
WORKSHEET" .
Continue “Road Test”.
2. CHECK SHIFT-UP (D1 TO D2 )
Check shift-up (D
1 to D2 ).
Specified speed when shifting from D
1 to D2 (Throttle position: half throttle). Refer to AT- 5 4 , "Vehicle Speed
Which Gear Shifting Occurs" .
Read gear position, throttle opening and vehicle speed. Refer to AT- 7 0 , "
DATA MONITOR MODE" .
Does A/T shift from D
1 to D2 at the specified speed?
YES >> GO TO 3.
NO >>
Mark the box AT- 1 8 4 , "A/T Does Not Shift: D1 → D2 or Does Not Kickdown: D4 → D2" on the
AT- 3 8 , "
DIAGNOSTIC WORKSHEET" .
Continue “Road Test”.
3. CHECK SHIFT-UP (D2 TO D3 )
Check shift-up (D
2 to D3 ).
Specified speed when shifting from D
2 to D3 (Throttle position: half throttle). Refer to AT- 5 4 , "Vehicle Speed
Which Gear Shifting Occurs" .
Read gear position, throttle opening and vehicle speed. Refer to AT- 7 0 , "
DATA MONITOR MODE" .
Does A/T shift from D
2 to D3 at the specified speed?
YES >> GO TO 4.
NO >>
Mark the box AT- 1 8 6 , "A/T Does Not Shift: D2 → D3" on the AT- 3 8 , "DIAGNOSTIC WORK-
SHEET" .
Continue “Road Test”.
4. CHECK SHIFT-UP (D3 TO D4 )
Check shift-up (D
3 to D4 ).
Specified speed when shifting from D
3 to D4 (Throttle position: half throttle). Refer to AT- 5 4 , "Vehicle Speed
Which Gear Shifting Occurs" .
Read gear position, throttle opening and vehicle speed. Refer to AT- 7 0 , "
DATA MONITOR MODE" .
Does A/T shift from D
3 to D4 at the specified speed?
YES >> GO TO 5.
NO >>
Mark the box AT- 1 8 8 , "A/T Does Not Shift: D3 → D4" on the AT- 3 8 , "DIAGNOSTIC WORK-
SHEET" .
Continue “Road Test”. ATF operating temperature: 50 - 80°C (122 - 176°F)
TROUBLE DIAGNOSIS
AT-61
D
E
F
G
H
I
J
K
L
MA
B
AT
Slips/Will Not
EngageRaces extremely
fast or slips in
changing from D
3
to D
2 when
depressing pedal. ON vehicle1. A/T fluid levelAT- 1 4
2. Accelerator pedal position sensor
EC-272*1, EC-652*2
3. Line pressure testAT- 4 6
4. Line pressure solenoid valveAT- 1 2 6
5. Shift solenoid valve BAT- 9 5
6. Control valve assemblyAT- 2 2 5
OFF vehicle7. Brake bandAT- 3 2 98. High clutchAT- 3 0 1
Races extremely
fast or slips in
changing from D
4
or D
3 to D 1
when depressing
pedal.ON vehicle1. A/T fluid levelAT- 1 4
2. Accelerator pedal position sensor
EC-272*1, EC-652*2
3. Line pressure testAT- 4 6
4. Line pressure solenoid valveAT- 1 2 6
5. Shift solenoid valve AAT- 9 0
6. Shift solenoid valve BAT- 9 5
7. Control valve assemblyAT- 2 2 5
OFF vehicle8. Forward clutchAT- 3 0 79. Forward one-way clutchAT- 3 1 9
10. Low one-way clutchAT- 2 5 5
Vehicle will not
run in any posi-
tion.ON vehicle1. A/T fluid levelAT- 1 4
2. A/T positionAT- 2 1 5
3. Line pressure testAT- 4 6
4. Line pressure solenoid valveAT- 1 2 6
OFF vehicle5. Oil pumpAT- 2 7 5
6. High clutchAT- 3 0 1
7. Brake bandAT- 3 2 9
8. Low & reverse brakeAT- 3 1 5
9. Torque converterAT- 2 5 5
10. Parking componentsAT- 2 4 6
OthersEngine cannot be
started in “P” and
“N” positions.
AT-175
ON vehicle1. Ignition switch and starterPG-3
, SC-14 .
2. A/T positionAT- 2 1 5
3. PNP switchAT- 1 6 1
Engine starts in
positions other
than “P” and “N”.ON vehicle1. A/T positionAT- 2 1 5
2. PNP switchAT- 1 6 1
Transaxle noise
in “P” and “N”
positions.ON vehicle1. A/T fluid levelAT- 1 4
2. Line pressure testAT- 4 6
3. Accelerator pedal position sensor
EC-272*1, EC-652*2
4. Vehicle speed sensor·A/T (Revolution
sensor) and vehicle speed sensor·MTRAT- 8 0, AT- 8 6
OFF vehicle5. Oil pumpAT- 2 7 56. Torque converterAT- 2 5 5
Items Symptom Condition Diagnostic item Reference page
TROUBLE DIAGNOSIS
AT-63
D
E
F
G
H
I
J
K
L
MA
B
AT
OthersMaximum speed
not attained.
Acceleration
poor.ON vehicle1. A/T fluid levelAT- 1 4
2. PNP switchAT- 1 6 1
3. 3rd position switchAT- 1 6 1
4. Accelerator pedal position sensor
EC-272*1, EC-652*2
5. Vehicle speed sensor·A/T (Revolution
sensor) and vehicle speed sensor·MTRAT- 8 0, AT- 8 6
6. Shift solenoid valve AAT- 9 0
7. Shift solenoid valve BAT- 9 5
8. Control valve assemblyAT- 2 2 5
OFF vehicle9. Reverse clutchAT- 2 9 6
10. High clutchAT- 3 0 1
11. Brake bandAT- 3 2 9
12. Low & reverse brakeAT- 3 1 5
13. Oil pumpAT- 2 7 5
14. Torque converterAT- 2 5 5
Transaxle noise
in “D”, “3”, “2”, “1”
and “R” positions.ON vehicle 1. A/T fluid levelAT- 1 4
OFF vehicle 2. Torque converterAT- 2 5 5
Engine brake
does not operate
in “1” position.ON vehicle1. PNP switchAT- 1 6 1
2. A/T positionAT- 2 1 5
3. Vehicle speed sensor·A/T (Revolution
sensor) and vehicle speed sensor·MTRAT- 8 0, AT- 8 6
4. Control valve assemblyAT- 2 2 5
5. Overrun clutch solenoid valveAT- 1 0 0
OFF vehicle6. Overrun clutchAT- 3 0 77. Low & reverse brakeAT- 3 1 5
Transaxle over-
heats.ON vehicle1. A/T fluid levelAT- 1 4
2. Engine idle speed
EC-45*1, EC-387*2
3. Accelerator pedal position sensor
EC-272*1, EC-652*2
4. Line pressure testAT- 4 6
5. Line pressure solenoid valveAT- 1 2 6
6. Control valve assemblyAT- 2 2 5
OFF vehicle7. Oil pumpAT- 2 7 5
8. Reverse clutchAT- 2 9 6
9. High clutchAT- 3 0 1
10. Brake bandAT- 3 2 9
11. Forward clutchAT- 3 0 7
12. Overrun clutchAT- 3 0 7
13. Low & reverse brakeAT- 3 1 5
14. Torque converterAT- 2 5 5
Items Symptom Condition Diagnostic item Reference page
AT-64
TROUBLE DIAGNOSIS
*1: QR engine
*2: VQ engine
TCM Terminals and Reference ValueBCS0010C
TCM CONNECTOR TERMINAL LAYOUT
TCM INSPECTION TABLE
Data are reference value and are measured between each terminal and ground.
OthersATF shoots out
during operation.
White smoke
emitted from
exhaust pipe dur-
ing operation.ON vehicle 1. A/T fluid levelAT- 1 4
OFF vehicle2. Reverse clutchAT-296
3. High clutchAT-301
4. Brake bandAT-329
5. Forward clutchAT-307
6. Overrun clutchAT-307
7. Low & reverse brakeAT-315
Offensive smell at
fluid charging
pipe.ON vehicle 1. A/T fluid levelAT- 1 4
OFF vehicle2. Torque converterAT-255
3. Oil pumpAT-275
4. Reverse clutchAT-296
5. High clutchAT-301
6. Brake bandAT-329
7. Forward clutchAT-307
8. Overrun clutchAT-307
9. Low & reverse brakeAT-315
Items Symptom Condition Diagnostic item Reference page
SCIA0495E
Terminal Wire color Item ConditionJudgement stan-
dard (Approx.)
1 G/RLine pressure sole-
noid valveWhen releasing accelerator pedal
after warming up engine.1.5 - 3.0 V
When depressing accelerator pedal
fully after warming up engine.0V
2W/BLine pressure sole-
noid valve (with drop-
ping resistor)When releasing accelerator pedal
after warming up engine.4 - 14 V
When depressing accelerator pedal
fully after warming up engine.0V
3 G/BTorque converter
clutch solenoid valveWhen A/T performs lock-up. 8 - 15 V
When A/T does not perform lock-up. 0 V
5 L CAN-H — —
6P CAN-L — —
AT-126
LINE PRESSURE SOLENOID VALVE
LINE PRESSURE SOLENOID VALVEPFP:31940
DescriptionBCS0012I
Line pressure solenoid valve regulates oil pump discharge pressure to suit the driving condition in response to
a signal sent from TCM.
The line pressure duty cycle value is not consistent when the closed throttle position switch is ON. To
confirm the line pressure duty cycle at low-pressure, accelerator (throttle) should be open until the
closed throttle position switch is “OFF”.
CONSULT-II Reference ValveBCS0026L
On Board Diagnosis LogicBCS0012J
Diagnostic trouble code “LINE PRESSURE S/V” with CONSULT-II or 11th judgement flicker without CON-
SULT-II is detected when TCM detects an improper voltage drop when it tries to operate the solenoid valve.
Possible CauseBCS0012K
Harness or connector
(Solenoid circuit is open or shorted.)
Line pressure solenoid valve
DTC Confirmation ProcedureBCS0012L
CAUTION:
If performing this “DTC Confirmation Procedure” again, always turn ignition switch OFF and wait at
least 10 seconds before continuing.
After the repair, perform the following procedure to confirm that the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch ON. (Do not start engine.)
2. Select “DATA MONITOR” mode for “A/T” with CONSULT-II.
3. Depress accelerator pedal completely and wait at least 1 sec-
ond.
4. If DTC is detected, go to AT- 1 2 9 , "
Diagnostic Procedure" .
WITHOUT CONSULT-II
1. Start engine.
2. With brake pedal depressed, shift the lever from “P” → “N” → “D” → “N” → “P” positions.
3. Perform self-diagnosis. Refer to AT- 7 6 , "
Diagnostic Procedure Without CONSULT-II" .
4. If the check result is NG, go to AT- 1 2 9 , "
Diagnostic Procedure" .
Item name Condition Display value (Approx.)
LINE PRES DTYSmall throttle opening (Low line pressure) ⇔ Large throttle opening
(High line pressure)0% ⇔ 92%
BCIA0031E
AT-146
A/T 4TH GEAR FUNCTION
A/T 4TH GEAR FUNCTIONPFP:31940
DescriptionBCS0013G
This malfunction will not be detected while A/T CHECK indicator lamp is indicating another self-diagnosis
malfunction.
This malfunction is detected when A/T does not shift into fourth gear position or the torque converter
clutch does not lock up as instructed by TCM. This is not caused by electrical malfunction (circuits open or
shorted) but by mechanical malfunction such as control valve sticking, improper solenoid valve operation,
malfunctioning oil pump or torque converter clutch, etc.
CONSULT-II Reference Value BCS0026N
On Board Diagnosis LogicBCS0013H
This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by TCM
as follows:
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from ECM
C: Gear ratio determined as gear position which TCM supposes
If the actual gear position is much lower than the position (4th) supposed by TCM, the slip ratio will be
much less than normal. In case the ratio does not reach the specified value, TCM judges this diagnosis
malfunction.
This malfunction will be caused when shift solenoid valve B is stuck closed.
Gear positions supposed by TCM are as follows.
In case of gear position with no malfunctions: 1, 2, 3 and 4 positions
In case of gear position with shift solenoid valve A stuck open: 2, 2, 3 and 3* position
In case of gear position with shift solenoid valve B stuck closed: 1, 2, 2 and 1* positions to each gear
position above
*: “A/T 4TH GR FNCTN” is detected.
Diagnostic trouble code “A/T 4TH GR FNCTN” with CONSULT-II is detected when A/T cannot be shifted
to the 4th gear position even if electrical circuit is good.
Possible CauseBCS0013I
Shift solenoid valve A
Shift solenoid valve B
Line pressure solenoid valve
Each clutch
Hydraulic control circuit
Gear position 1 2 3 4
Shift solenoid valve A ON (Closed) OFF (Open) OFF (Open) ON (Closed)
Shift solenoid valve B ON (Closed) ON (Closed) OFF (Open) OFF (Open)
Item name Condition Display value (Approx.)
LINE PRES DTYSmall throttle opening (Low line pressure) ⇔ Large throttle opening
(High line pressure)0% ⇔ 92%
A/T TCC S/V FUNCTION (LOCK-UP)
AT-151
D
E
F
G
H
I
J
K
L
MA
B
AT
A/T TCC S/V FUNCTION (LOCK-UP)PFP:31940
DescriptionBCS0013L
This malfunction is detected when A/T does not shift into fourth gear position or torque converter clutch
does not lock-up as instructed by TCM. This is not caused by electrical malfunction (circuits open or
shorted) but by mechanical malfunction such as control valve sticking, improper solenoid valve operation,
malfunctioning oil pump or torque converter clutch, etc.
CONSULT-II Reference ValueBCS0026O
On Board Diagnosis LogicBCS0013M
This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by TCM
as follows:
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from ECM
C: Gear ratio determined as gear position which TCM supposes
If the actual gear position is much lower than the position (4th) supposed by TCM, the slip ratio will be
much less than normal. In case the ratio does not reach the specified value, TCM judges this diagnosis
malfunction.
This malfunction will be caused when shift solenoid valve B is stuck closed.
Gear positions supposed by TCM are as follows.
In case of gear position with no malfunctions: 1, 2, 3 and 4 positions
In case of gear position with shift solenoid valve B stuck closed: 1, 2, 2 and 1 positions to each gear posi-
tion above
Diagnostic trouble code “A/T TCC S/V FNCTN” with CONSULT-II is detected when A/T cannot perform
lock-up even if electrical circuit is good.
Possible CauseBCS0013N
Line pressure solenoid valve
Torque converter clutch solenoid valve
Each clutch
Hydraulic control circuit
Item name Condition Display value (Approx.)
TCC S/V DUTY Lock-up OFF ⇔ Lock-up ON 4% ⇔ 94%
LINE PRES DTYSmall throttle opening (Low line pressure) ⇔ Large throttle opening
(High line pressure)0% ⇔ 92%
AT-182
TROUBLE DIAGNOSIS FOR SYMPTOMS
6. CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT- 2 5 5 , "
Disassembly" .
2. Check A/T fluid condition. Refer to AT- 4 3 , "
A/T Fluid Condition Check" .
OK or NG
OK >> GO TO 7.
NG >> GO TO 5.
7. SYMPTOM CHECK
Check again. Refer to AT- 4 8 , "
Check at Idle" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 8.
8. CHECK TCM
1. Check TCM input/output signals. Refer to AT- 6 4 , "
TCM Terminals and Reference Value" .
2. 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.
Vehicle Cannot Be Started From D1BCS0014G
SYMPTOM:
Vehicle cannot be started from D1 on “Cruise Test — Part 1” and “Cruise Test — Part 2”.
DIAGNOSTIC PROCEDURE
1. SYMPTOM CHECK
Check symptom. Refer to AT- 4 8 , "
Check at Idle" .
Does vehicle creep backward in
“R” position?
YES >> GO TO 2.
NO >> Go to AT- 1 7 9 , "
Vehicle Does Not Creep Backward in “R” Position" .
2. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to AT- 6 9 , "
SELF-DIAGNOSTIC RESULT MODE" or AT- 7 6 , "Diagnostic Proce-
dure Without CONSULT-II" .
Is any malfunction detected by self-diagnostic results?
YES >> Check the malfunctioning systems. Refer to AT- 6 9 , "SELF-DIAGNOSTIC RESULT MODE" or AT-
77, "Judgement of Self-Diagnosis Code" .
NO >> GO TO 3.
3. CHECK ACCELERATOR PEDAL POSITION SENSOR
Check accelerator pedal position sensor. Refer to EC-272, "
DTC P2138 APP SENSOR" (QR engine) or EC-
652, "DTC P2138 APP SENSOR" (VQ engine).
OK or NG
OK >> GO TO 4.
NG >> Repair or replace accelerator pedal position sensor.