Toyota Sequoia (2005). Manual - part 204

ECM command gearshift

Shift solenoid valve S1

1st

2nd

3rd

4th

5th

OFF

ON

ON

OFF OFF

–

DIAGNOSTICS

AUTOMATIC TRANSMISSION

DI–611

805

INSPECTION PROCEDURE

HINT:
Performing the ACTIVE TEST using the hand–held tester allows the relay, VSV, actuator and so on to oper-
ate without parts removal. Performing the ACTIVE TEST as the first step of troubleshooting is one method
to shorten labor time.
It is possible to display the DATA LIST during the ACTIVE TEST.
(a)

Warm up the engine.

(b)

Turn the ignition switch off.

(c)

Connect the hand–held tester to the DLC3.

(d)

Turn the ignition switch to the ON position.

(e)

Turn on the tester.

(f)

Select the item ”DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST”.

(g)

According to the display on the tester, perform the ”ACTIVE TEST”.

HINT:
While driving, the shift position can be forcibly changed with the hand–held tester.
Comparing the shift position commanded by the ACTIVE TEST with the actual shift position enables you
to confirm the problem (See page 

DI–567

).

Item

Test Details

Diagnostic Note

SHIFT

[Test Details]

Operate the shift solenoid valve and set each shift position by yourself.

[Vehicle Condition]

Less than 50 km/h (31 mph)

[Others]

Press ”

→

” button: Shift up

Press ”

←

” button: Shift down

Possible to check the operation of

the shift solenoid valves.

HINT:

This test can be conducted when the vehicle speed is 50 km/h (31 mph) or less.

The 4th to 5th up–shiftings must be performed with the accelerator pedal released.

The 5th to 4th down–shiftings must be performed with the accelerator pedal released.

Do not operate the accelerator pedal for at least 2 seconds after shifting and do not shift successively.

The shift position commanded by the ECM is shown in the DATA LIST (SHIFT) display on the hand–
held tester.

The shift solenoid valve S1 is turned on/off normally when the shift lever is in the D position:

DI–612

–

DIAGNOSTICS

AUTOMATIC TRANSMISSION

806

1

Check other DTCs output (in addition to DTC P0751).

PREPARATION:
(a)

Turn the ignition switch off.

(b)

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

(c)

Turn the ignition switch to the ON position.

(d)

Turn on the tester.

(e)

Select the item ”DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES”.

CHECK:
Read the DTCs using the OBD II scan tool or the hand–held tester.
RESULT:

Display (DTC output)

Proceed to

Only ”P0751” is output

A

”P0751” and other DTCs

B

HINT:
If any other codes besides ”P0751” are output, perform troubleshooting for those DTCs first.

B

Go to DTC chart (See page 

DI–573

).

A

D11991

Shift solenoid S1:

(+)

(–)

–

DIAGNOSTICS

AUTOMATIC TRANSMISSION

DI–613

807

2

Check shift solenoid valve S1 operation.

PREPARATION:
Remove the shift solenoid valve S1 (See page 

AT–10

).

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

Tester Connection

Specified Condition

20



C (68



F)

Solenoid Connector (S1) – Solenoid

Body (S1)

11 to 15 

Ω

CHECK:
Connect the positive (+) lead to the terminal of the solenoid con-
nector, and the negative (–) lead to the solenoid body.
OK:

The solenoid makes an operating sound.

NG

Replace shift solenoid valve S1
(See page 

AT–10

).

OK

3

Inspect valve body 

(See page 

AT–10

).

OK:

There are no foreign objects on each valve.

NG

Repair or replace valve body.

OK

Repair or replace transmission (See page 

AT–25

).

DI–614

–

DIAGNOSTICS

AUTOMATIC TRANSMISSION

808

DTC

P0756

Shift Solenoid ”B” Performance 
(Shift Solenoid Valve S2)

SYSTEM DESCRIPTION

The ECM uses signals from the output shaft speed sensor and input speed sensor to detect the actual gear
position (1st, 2nd, 3rd, 4th or 5th gear).
Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical
problems of the shift solenoid valves, valve body or automatic transmission (clutch, brake or gear, etc.).

DTC No.

DTC Detection Condition

Trouble Area

P0756

The gear required by the ECM does not match the actual gear

when driving (2–trip detection logic)

Shift solenoid valve S2 remains open or closed

Valve body is blocked

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

MONITOR 

DESCRIPTION

This DTC indicates ”stuck ON malfunction” or ”stuck OFF malfunction” of the shift solenoid valve S2.
The ECM commands gear shifts by turning the shift solenoid valves ”ON/OFF”. When the gear position com-
manded by the ECM and the actual gear position are not the same, the ECM illuminates the MIL and stores
the DTC.

MONITOR STRATEGY

R l t d DTC

P0756

Shift solenoid valve S2/OFF malfunction

Related DTCs

P0756

Shift solenoid valve S2/ON malfunction

Main

Shift solenoid valve S2

Required sensors/Components

Sub

Vehicle speed sensor, Throttle position sensor, Speed sensor (NT), Speed

sensor (NO)

Frequency of operation

Continuous

OFF malfunction (A), (B), (C)

0.4 sec.

OFF malfunction (D)

Immediate

Duration

ON malfunction (A) and (B)

0.4 sec.

Duration

ON malfunction (C)

3 sec.

ON malfunction (D)

0.5 sec.

MIL operation

2 driving cycles

Sequence of operation

None

DIDJD–01