1986 TOYOTA LAND CRUISER automatic transmission

D01769
- DIAGNOSTICSAUTOMATIC TRANSMISSION
DI-487
680 Author
: Date
:
2004 LAND CRUISER (RM1071U)
DTC P2757Torque Converter Clutch Pressure Control Solenoid
Performance(Shift Solenoid Valve SLU)
SYSTEM DESCRIPTION
The ECM uses the signals from the Throttle Position Sensor
and Air-flow Meter to monitor the engagement condition of the
lock-up clutch.
Then the ECM compares the engagement condition of the
lock-up clutch with the lock-up schedule in the ECM memory
to detect mechanical trouble of the shift solenoid valve SLU,
valve body, torque converter clutch and automatic transmission
assembly (clutch, brake or gear etc.).
DTC No.DTC Detecting ConditionTrouble Area
P2757
Lock-up does not occur when driving in the lock-up range
(normal driving at 80 km/h [50 mph]), or lock-up remains ON
in the lock-up OFF range.
(2-trip detection logic)
Shift solenoid valve SLU is stuck open or closed

Valve body blocked up or stuck

Lock-up clutch

Automatic transmission assembly
MONITOR DESCRIPTION
The ECM controls the oil pressure to the lock-up clutch based on engine-load information from the throttle
position sensor, crankshaft position sensor, input speed sensor, and the oil pressure sensor for shift-sole-
noid SLU. The ECM commands the shift-solenoid SLU using a duty-cycle control signal. In turn, the shift
solenoid operates the lock-up control valve and causes lock-up or flexible lock-up of the torque converter
clutch.
To monitor the condition of the lock up clutch, the ECM monitors the signals from the input speed sensor,
crank position sensor, the throttle position sensor, and air flow meter. The ECM uses this information to deter-
mine when the vehicle's torque converter clutch should be locked-up. The ECM can detect many mechani-
cal problems in the shift solenoids, valve body, and the transmission clutches, brakes, and gears. If the ECM
detects that the torque converter clutch locked below the minimum lock-up speed, it will illuminate the MIL
and store the DTC.
MONITOR STRATEGY
RltdDTCP2757Shift solenoid valve SLU/OFF malfunctionRelated DTCsP2757Shift solenoid valve SLU/ON malfunction
MainShift solenoid valve SLU
Required sensors/ComponentsSubValve body, Vehicle speed sensor, Throttle position sensor, Speed sensor
(NT), Speed sensor (NO)
Frequency of operationContinuous
DtiOFF malfunction2 sec.DurationON malfunction1.8 sec.
MIL operation2 driving cycles
Sequence of operationNone
DIB3L-02

DI-488
- DIAGNOSTICSAUTOMATIC TRANSMISSION
681 Author
: Date
:
2004 LAND CRUISER (RM1071U)
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The following items are common to all conditions below: OFF malfunction and ON malfunction
The monitor will run whenever the follow-
ing DTCs are not present.See page DI-361
Turbine speed sensor (NT) circuit
Output speed sensor (NO) circuit
Shift solenoid ºAº (S1) circuit
Shift solenoid ºBº (S2) circuitThere is no malfunction in the circuits shown on the leftShift solenoid ºEº (SR) circuitThere is no malfunction in the circuits shown on the left.
Torque converter clutch pressure control
solenoid circuit
KCS sensor circuit
ETCS (Electric throttle control system)Not system down
Transmission shift positionºDº
ECT (Engine coolant temperature)40°C (104°F) or more-
Spark advance from Max. retard timing by
KCS control0° CA or more-
EngineRunning
ECM selected gear4th or 5th
Vehicle speed25 km/h or more-
Shift solenoid ºAº (S1) circuit
Shift solenoid ºBº (S2) circuitTh i lf ti i th i it h th l ftPressure control solenoid ºBº (SL2) circuitThere is no malfunction in the circuits shown on the left.
1-2 Shift valve
Transfer neutral position switchOFF
Transfer rangeºHIGHº*1
Transfer range ºHIGHº *1 (This condition is applied only 4WD)
*1 Following conditions met
Vehicle speed sensor ºAº circuitTh i lf ti i th i it h th l ft Output shaft speed sensor circuitThere is no malfunction in the sensor circuits shown on the left.
Transfer output speed143 rpm or more-
NO/NOtf (Transfer input speed/Transfer
output speed)0.9 or moreLess than 1.1
OFF malfunction
ECM lock-up commandON
(SLU pressure: 513kpa or more)
Vehicle speed-Less than 100 km/h (62 mph)
ON malfunction
ECM lock-up commandOFF
(SLU pressure: less than 4kpa)
Throttle valve opening angle9% or more-
Vehicle speed-Less than 60 km/h (38 mph)

D12795
12
(-)(+)
12
- DIAGNOSTICSAUTOMATIC TRANSMISSION
DI-489
682 Author
: Date
:
2004 LAND CRUISER (RM1071U)
TYPICAL MALFUNCTION THRESHOLDS
Detection criteriaThreshold
OFF malfunction
Engine speed - Turbine speed70 rpm or more
ON malfunction
It is necessary 2 detections/one driving cycle
1st detection; temporary flag ON
2nd detection; pending fault code ON
Vehicle speed must be under 10 km/h (6 mph) once before 2nd detection
|Engine speed - Turbine speed|Less then 35 rpm
COMPONENT OPERATING RANGE
ParameterStandard value
Speed sensor (NT)Input speed is equal to engine speed when lock-up ON.
INSPECTION PROCEDURE
1 Check shift solenoid valve SLU operation.
PREPARATION:
(a) Jack up the vehicle.
(b) Remove the oil pan.
(c) Remove the shift solenoid valve SLU.
CHECK:
(a) Measure the resistance between terminals 1 and 2 of so-
lenoid connector.
Standard: 5.0 to 5.6 W at 20°C (68°F)
(b) Connect the positive (+) lead with an 21 W bulb to terminal
2 of solenoid connector and negative (-) lead to terminal
1 of the solenoid valve connector, then check the move-
ment of the valve.
Standard: Solenoid sounds operation noise.
OK:
Standard
NG Replace the shift solenoid valve SLU
(See page AT-8).
OK

DI-490
- DIAGNOSTICSAUTOMATIC TRANSMISSION
683 Author
: Date
:
2004 LAND CRUISER (RM1071U)
2 Check valve body (See page DI-396).
NG Replace the valve body (See page AT-8).
OK
3 Check torque converter clutch (See page AT-34).
OK Repair or replace transmission (See page
AT-30).
NG
Replace the torque converter clutch
(See page AT-30).

Current flow to solenoid
Lock-up
Operation
Pressure
BE4056D00160
1 cycle ON
OFFDuty Ratio
=
A + B
A
y 100 (%) (*)
- DIAGNOSTICSAUTOMATIC TRANSMISSION
DI-491
684 Author
: Date
:
2004 LAND CRUISER (RM1071U)
DTC P2759Torque Converter Clutch Pressure Control Solenoid
Control Circuit Electrical(Shift Solenoid Valve SLU)
CIRCUIT DESCRIPTION
The amount of current flow to the solenoid is controlled by the
(*) duty ratio of the ECM output signal. The higher the duty ratio
becomes, the higher the lock-up hydraulic pressure becomes
during the lock-up operation.
(*) Duty Ratio
The duty ratio is the ratio of the period of continuity in one cycle.
For example, if A is the period of continuity in one cycle, and B
is the period of non-continuity, then
DTC No.DTC detection conditionTrouble Area
P2759
The following condition is detected. (1-trip detection logic)
SLU output signal's duty ON of 3.3 msec. or more with duty
ratio of least 95% lasts for 1 second.
Open or short in shift solenoid valve SLU circuit

Shift solenoid valve SLU

ECM
MONITOR DESCRIPTION
The ECM controls the oil pressure to the lock-up clutch based on engine-load information from the throttle
position sensor, crankshaft position sensor, input speed sensor, and the oil pressure sensor for shift-sole-
noid SLU. The ECM commands the shift-solenoid SLU using a duty-cycle control signal. In turn, the shift
solenoid operates the lock-up control valve and cause lock-up or flexible lock-up of the torque converter
clutch. The ECM illuminates the MIL and store the DTC when ECM detects an open or a short circuit malfunc-
tion in the shift solenoid valve SLU.
MONITOR STRATEGY
Related DTCsP2759Shift solenoid valve SLU/Range check
Required sensors/ComponentsShift solenoid valve SLU
Frequency of operationContinuous
Duration1 sec.
MIL operationImmediate
Sequence of operationNone
DIB3M-02

D12762
E1
Electronically Controlled
Transmission SolenoidECM
16 2
EB2 E7
SLU
-
P-G
B 215SLU+LG
EB3E7 P-G
B BRSLU+
SLU- 513 DI-492
- DIAGNOSTICSAUTOMATIC TRANSMISSION
685 Author
: Date
:
2004 LAND CRUISER (RM1071U)
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever the follow-
ing DTCs are not present.See page DI-361
Battery voltage10 V or more-
TYPICAL MALFUNCTION THRESHOLDS
Detection criteriaThreshold
Output signal duty100%
COMPONENT OPERATING RANGE
ParameterStandard value
Output signal dutyLess than 100%
WIRING DIAGRAM

1
152 3 4 5 6 7 8
9 10 11 12
13 14
D11994SLU+
SLU-
D12791SLU+SLU-
E5E6E7E8E9
- DIAGNOSTICSAUTOMATIC TRANSMISSION
DI-493
686 Author
: Date
:
2004 LAND CRUISER (RM1071U)
INSPECTION PROCEDURE
1 Check transmission wire.
PREPARATION:
Disconnect the transmission wire connector.
CHECK:
Measure resistance between SLU+ and SLU- of transmission
wire.
OK:
Resistance: 5.0 to 5.6 W at 20°C (68°F)
CHECK:
Measure resistance between terminals SLU+ and SLU- of the
transmission wire connector and body ground.
OK:
Resistance: 1 MW or higher
NG Go to step 3.
OK
2 Measure resistance between terminal SLU+ and SLU- of ECM connector.
PREPARATION:
(a) Connect the transmission wire connector.
(b) Disconnect the connector of the ECM.
CHECK:
Measure resistance between terminals SLU+ and SLU- of ECM
connector.
OK:
Resistance: 5.0 to 5.6 W at 20°C (68°F)
CHECK:
Measure resistance between terminals SLU+ and SLU- of the
ECM connector and body ground.
OK:
Resistance: 1 MW or higher
NG Repair or replace the harness or connector
(See page IN-36).
OK
Check and replace the ECM (See page
IN-36).

D12795
12
(-)(+)
12
DI-494
- DIAGNOSTICSAUTOMATIC TRANSMISSION
687 Author
: Date
:
2004 LAND CRUISER (RM1071U)
3 Check shift solenoid valve SLU.
PREPARATION:
(a) Jack up the vehicle.
(b) Remove the oil pan.
(c) Remove the shift solenoid valve SLU.
CHECK:
(a) Measure the resistance between terminals 1 and 2 of so-
lenoid connector.
Standard: 5.0 to 5.6 W at 20°C (68°F)
(b) Connect the positive (+) lead with an 21 W bulb to terminal
2 of solenoid connector and negative (-) lead to terminal
1 of the solenoid valve connector, then check the move-
ment of the valve.
Standard: Solenoid sounds operation noise.
OK:
Standard

NG Replace the shift solenoid valve SLU
(See page AT-8).
OK
Repair or replace the transmission wire
(See page AT-6).