Toyota Sequoia (2005). Manual - part 218

–

DIAGNOSTICS

AUTOMATIC TRANSMISSION

DI–667

861

DTC No.

DTC Detecting Condition

Trouble Area

P2740

(a) and (b) are detected momentarily within 0.5 sec. when
neither P2742 nor P2743 is detected (1–trip detection logic)

(a) ATF temperature sensor No.2 resistance is less than 25 

Ω

(

0.046 V

)

(b) ATF temperature sensor No.2 resistance is more than 156

k

Ω (

4.915 V

)

HINT:
Within 0.5 sec. the malfunction switches from (a) to (b) or from
(b) to (a)

Open or short in ATF temperature sensor No.2 circuit

Transmission wire (ATF temperature sensor No.2)

ECM

P2742

ATF temperature sensor No.2 resistance is less than 25 

Ω

(

0.046 V

) 

for 0.5 sec. or more (1–trip detection logic)

Short in ATF temperature sensor No.2 circuit

Transmission wire (ATF temperature sensor No.2)

ECM

P2743

ATF temperature No.2 sensor resistance is more than 156 k

Ω

(

4.915 V

)

 when 15 minutes or more after the engine start

DTC is detected for 0.5 sec. or more (1–trip detection logic)

Open in ATF temperature sensor No.2 circuit

Transmission wire (ATF temperature sensor No.2)

ECM

MONITOR DESCRIPTION

The Automatic Transmission Fluid (ATF) temperature sensor converts ATF temperature to an electrical re-
sistance value. Based on the resistance, the ECM determines the ATF temperature, and the ECM detects
an open or short in the AFT temperature circuit. If the resistance value of the ATF temperature is less than
25 

Ω (

0.046 V

)

 or more than 156 k

Ω (

4.915 V

)

, the ECM interprets this as a fault in the ATF sensor or wiring.

The ECM will turn on the MIL and store the DTC.

MONITOR STRATEGY

P2740

ATF temperature sensor/Range check (Fluttering)

Related DTCs

P2742

ATF temperature sensor/Range check (Low voltage)

Related DTCs

P2743

ATF temperature sensor/Range check (High voltage)

Required sensors/Components

ATF temperature sensor (TFT sensor)

Frequency of operation

Continuous

Duration

0.5 sec.

MIL operation

Immediate

Sequence of operation

None

TYPICAL ENABLING CONDITIONS

It

Specification

Item

Minimum

Maximum

The monitor will run whenever these

DTCs are not present.

See page 

DI–545

Range check (Fluttering, Low voltage)

The typical enabling condition is not avail-

able.

–

Range check (High voltage)

Time after engine start

15 min. or more

–

D14157

O

E1 Electronically Controlled 
Transmission Solenoid

OT–

O

OT+

L

OT2–

L

OT2+

G–W

G–W

G–W

G

B–L

G–W

2

1

10

9

E7

E7

E8

28

32

24

THO2

THO1

E2

ECM

DI–668

–

DIAGNOSTICS

AUTOMATIC TRANSMISSION

862

TYPICAL MALFUNCTION THRESHOLDS

Detection criteria

Threshold

Range check (Fluttering)

TFT (transmission fluid temperature) sensor voltage

Less than 0.046 V

or

More than 4.915 V

Range check (Low voltage)

TFT (transmission fluid temperature) sensor voltage

Less than 0.046 V

Range check (High voltage)

TFT (transmission fluid temperature) sensor voltage

More than 4.915 V

COMPONENT OPERATING RANGE

Parameter

Standard value

TFT (transmission fluid temperature) sensor

Atmospheric temperature to approx. 130

°

C (266

°

F)

WIRING DIAGRAM

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DIAGNOSTICS

AUTOMATIC TRANSMISSION

DI–669

863

INSPECTION PROCEDURE

HINT:
According to the DATA LIST displayed by the OBD II scan tool or hand–held tester, you can read the value
of the switch, sensor, actuator and so on without parts removal. Reading the DATA LIST as the first step of
troubleshooting  is one method to shorten labor time.
(a)

Warm up the engine.

(b)

Turn the ignition switch off.

(c)

Connect the OBD II scan tool or hand–held tester to the DLC3.

(d)

Turn the ignition switch to the ON position.

(e)

Push the ”ON” button of the OBD II scan tool or the hand–held tester.

(f)

When you use the hand–held tester:
Select the item ”DIAGNOSIS / ENHANCED OBD II / DATA LIST”.

(g)

According to the display on the tester, read the ”DATA LIST”.

Item

Measurement Item/

Range (display)

Normal Condition

AT FLUID TEMP 2

ATF Temp. Sensor Value/

min.: –40



C (–40



F)

max.: 215



C (419



F)

After Stall Test;
Approx. 80



C (176



F)

Equal to ambient temperature when cold soak

HINT:
When DTC P2742 is output and hand–held tester output is 150



C (302



F) or more, there is a short circuit.

When DTC P2743 is output and hand–held tester output is –40



C (–40



F), there is an open circuit.

Measure the resistance between terminal THO2 (OT2) and body ground.

Temperature Displayed

Malfunction

–40

°

C (–40

°

F)

Open circuit

150

°

C (302

°

F) or more

Short circuit

1

15

2

3

4

5

6

7

8

9

10

11

12

13

14

D11994

OT2+

OT2–

Transmission Wire Side:
(Connector Front View):

E1

DI–670

–

DIAGNOSTICS

AUTOMATIC TRANSMISSION

864

1

Inspect transmission wire (ATF temperature sensor No.2)

PREPARATION:
Disconnect the transmission wire connector from the transmis-
sion.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:

Tester Connection

Specified Condition

1 (OT2–) – 9 (OT2+)

25 

Ω

 to 156 k

Ω

1 (OT2–) – Body ground

10 k

Ω

 or higher

9 (OT2+) – Body ground

10 k

Ω

 or higher

HINT:
If the resistance is out of the specified range with either the ATF
temperature shown in the table below, the driveability of the ve-
hicle may decrease.

ATF Temperature

Specified Condition

20

°

C (68

°

F)

3 to 4 k

Ω

110°

C (230

°

F)

0.22 to 0.28 k

Ω

NG

Repair or replace the transmission wire 
(ATF temperature sensor No.2)
(See page 

AT–7

).

OK