Toyota Sequoia (2005). Manual - part 219

D14161

E8

E7

E6

E5

E4

ECM:

THO2

E2

–

DIAGNOSTICS

AUTOMATIC TRANSMISSION

DI–671

865

2

Check harness and connector (Transmission wire – ECM)

PREPARATION:
(a)

Connect the transmission wire connector.

(b)

Disconnect the connector of the ECM.

CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:

Tester Connection

Specified Condition

E7 – 32 (THO2) – E8 – 28 (E2)

25 

Ω

 to 156 k

Ω

CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:

Tester Connection

Specified Condition

E7 – 32 (THO2) – Body ground

10 k

Ω

 or higher

E8 – 28 (E2) – Body ground

↑

NG

Repair or replace the harness or connector
(See page 

IN–35

).

OK

Replace the ECM (See page 

SF–80

).

D14175

G23415

D14176

Lock–up
Operation 
Pressure

Current Flow to Solenoid

DI–672

–

DIAGNOSTICS

AUTOMATIC TRANSMISSION

866

DTC

P2757

Torque Converter Clutch Pressure Control Solenoid
Performance(Shift Solenoid Valve SLU)

SYSTEM DESCRIPTION

The ECM uses the signals from the throttle position sensor, Air–
flow meter, turbine (input) speed sensor, output speed sensor
and crankshaft position sensor 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 a mechanical problems of the shift solenoid valve
SLU, valve body and torque converter clutch.

DTC No.

DTC Detection Condition

Trouble 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 remains open or closed

Valve body is blocked

Torque converter clutch

Automatic transmission (clutch, brake or gear, etc.)

Line pressure is too low

DIDJO–01

–

DIAGNOSTICS

AUTOMATIC TRANSMISSION

DI–673

867

MONITOR DESCRIPTION

Torque converter lock–up is controlled by the ECM based on the turbine (input) speed sensor NT, output
speed sensor SP2, engine rpm, engine load, engine temperature, vehicle speed, transmission temperature,
and gear selection. The ECM determines the lock–up status of the torque converter by comparing the engine
rpm (NE) to the input turbine rpm (NT). The ECM calculates the actual transmission gear by comparing input
turbine rpm (NT) to output shaft rpm (SP2). When conditions are appropriate, the ECM requests ”lock–up”
by applying control voltage to the shift solenoid SLU. When the SLU is turned on, it applies pressure to the
lock–up relay valve and locks the torque converter clutch.
If the ECM detects no lock–up after lock–up has been requested or if it detects lock–up when it is not re-
quested, the ECM interprets this as a fault in the shift solenoid valve SLU or lock–up system performance.
The ECM will turn on the MIL and store the DTC.
Example:
When any of the following is met, the system judges it as a malfunction.
(a)

There is a difference in rotation between the input side (engine speed) and output side (input turbine
speed) of the torque converter when the ECM commands lock–up.
(Engine speed is at least 70 rpm greater than input turbine speed.)

(b)

There is no difference in rotation between the input side (engine speed) and output side (input turbine
speed) of the torque converter when the ECM commands lock–up off.
(The difference between engine speed and input turbine speed is less than 35 rpm.)

MONITOR STRATEGY

R l t d DTC

P2757

Shift solenoid valve SLU/OFF malfunction

Related DTCs

P2757

Shift solenoid valve SLU/ON malfunction

Main

Shift solenoid valve SLU

Required sensors/Components

Sub

Valve body, Vehicle speed sensor, Throttle position sensor, Speed sensor

(NT), Speed sensor (NO)

Frequency of operation

Continuous

OFF malfunction (A)

2 sec.

Duration

OFF malfunction (B)

0.4 sec.

Duration

ON malfunction

1.8 sec.

MIL operation

2 driving cycles

Sequence of operation

None

TYPICAL ENABLING CONDITIONS

It

Specification

Item

Minimum

Maximum

All:

Turbine speed sensor circuit

Not circuit malfunction

Output speed sensor circuit

Not circuit malfunction

Shift solenoid valve S1 circuit

Not circuit malfunction

Shift solenoid valve S2 circuit

Not circuit malfunction

Shift solenoid valve SR circuit

Not circuit malfunction

Torque converter clutch pressure control

solenoid circuit

Not circuit malfunction

KCS sensor circuit

Not circuit malfunction

ETCS (Electric throttle control system)

Not system down

Transmission range

”D”

DI–674

–

DIAGNOSTICS

AUTOMATIC TRANSMISSION

868

ECT (Engine coolant temperature)

40

°

C (104

°

F) or more

–

Spark advance from Max. retard timing by

KCS control

0

°

 

CA or more

–

Engine

Starting

ECM selected gear

4th or 5th

Vehicle speed

25 km/h (15.5 mph) or more

–

Shift solenoid valve S1 circuit

Not on malfunction

Shift solenoid valve S2 circuit

Not on malfunction

Shift solenoid valve SL2 circuit

Not on malfunction

1–2 Shift valve

Not on malfunction

Transfer neutral position switch

OFF

Transfer range

”HIGH”

*1

Transfer range ”HIGH” *1 (This condition is applied only 4WD)

*1 Following conditions met

 Vehicle speed sensor circuit

Not circuit malfunction

 Output shaft speed sensor circuit

Not circuit malfunction

 Transfer output speed

143 rpm or more

–

 NO/NOtf (Transfer input speed/Transfer

output speed)

0.9 to 1.1

OFF malfunction (A)

ECM lock–up command

ON

(SLU pressure: 513kpa or more)

Vehicle speed

–

Less than 100 km/h (62.2 mph)

OFF malfunction (B)

ECM selected gear

2nd

Vehicle speed

2 km/h (1.2 mph) or more

–

Output speed

2nd 

→

 1st down shift point or more

–

Throttle valve opening angle

7.0% or more at 2,000 rpm

(Conditions vary with engine speed)

–

ON malfunction

ECM lock–up command

OFF

(SLU pressure: less than 4kpa)

Throttle valve opening angle

9% or more

–

Vehicle speed

–

Less than 60 km/h (37.3 mph)