Toyota Sequoia (2005). Manual - part 177

A19655

A20059

STSW

ACCR

STAR

(NE)
Engine Speed

Starter

Park/Neutral
Position SW

N

P

ST Relay

ACC Cut 
Relay

Ignition 
SW

ACC

ST2

ACCR

STSW

STAR

Battery

ECM

–

DIAGNOSTICS

ENGINE

DI–503

697

Cranking Hold Function Circuit

CIRCUIT DESCRIPTION

The starter is controlled by the ECM, when the ECM detects a start signal (STSW) from the ignition switch,
this system monitors the engine speed (NE) and continues to operate the starter until it has determined that
the engine has started (engine speed reaches approximately 500 rpm). If the engine is already running and
the ignition switch is turned to START, the ECM will not operate the starter.

WIRING DIAGRAM

Refer to DTC P0617 on page 

DI–298

.

INSPECTION PROCEDURE
Hand–held tester:

1

Check operation of engine cranking.

CHECK:
When turning the ignition switch to the START position, check whether the starter motor starts.
OK:

Starter motor starts.

OK

Check for intermittent problems (See page 

DI–11

).

NG

DID8M–01

B17411

STA (+)

E1 (–)

STSW(+)

E6

DI–504

–

DIAGNOSTICS

ENGINE

698

2

Connect hand–held tester, and check STA signal.

PREPARATION:
(a)

Connect the hand–held tester to the DLC3.

(b)

Turn the ignition switch ON, and push the hand–held tester main switch ON.

(c)

Enter the following menu: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / STARTER SIG.

CHECK:
Read the STA signal on the hand–held tester while the starter operates.
OK:

Ignition Switch Position

ON

START

STARTER SIG

OFF

ON

NG

Go to step 5.

OK

3

Check voltage between terminal STAR, STSW and E1 of ECM connector.

CHECK:
Measure the voltage between the terminals of the E6 ECM con-
nectors, while cranking the engine (ignition switch START posi-
tion).
OK:

Standard:

Tester Connection

Specified Condition

STA (E6–11) – E1 (E6–1)

9 to 14 V

STSW (E6–12) – E1 (E6–1)

9 to 14 V

RESULT:

Terminal STAR

Terminal STSW

Proceed to

9 to 14 V

9 to 14 V

A

0 V

9 to 14 V

B

0 V

0 V

C

B

Replace ECM (See page 

SF–80

).

C

Go to step 9.

A

D14154

Component Side:

A19288

–

DIAGNOSTICS

ENGINE

DI–505

699

4

Check park/neutral position switch.

PREPARATION:
Remove the P1 park/neutral position switch connector.
CHECK:
Check resistance between each terminal shown below when
the shift lever is moved to each range.

Shift range

Terminal No. to continuity

P

1 – 3

6 – 9

R

2 – 3

–

N

3 – 5

6 – 9

D

3 – 7

–

2

3 – 4

–

L

3 – 8

–

OK:

Below 1 

Ω

NG

Replace the park/neutral position switch.

OK

Check and repair harness and connector be-
tween park/neutral position switch and ECM.

5

Check starter relay.

(a)

Remove the starter relay from the engine room R/B.

(b)

Inspect the starter relay.
Standard:

Tester Connection

Specified Condition

3 – 5

10 k

Ω

 or higher

3 – 5

Below 1 

Ω

(Apply battery voltage to terminals 1 and 2)

NG

Replace starter relay.

OK

A23563

Wire Harness Side

Park/Neutral position switch Connector

N1

A21559

Engine Room R/B No.2

Starter Relay

DI–506

–

DIAGNOSTICS

ENGINE

700

6

Check for open and short in harness and connector between park/neutral posi-
tion switch and starter relay.

(a)

Check the harness and the connector between the park/
neutral position switch connector and the starter relay.
(1)

Disconnect the park/neutral position switch con-
nector.

(2)

Remove the starter relay from the engine room R/B.

(3)

Check for resistance between the wire harness side
connectors.

Standard (Check for open):

Symbols (Terminal No.)

Specified condition

Park/Neutral position switch (N1–6) – Starter relay (1)

Below 1 

Ω

Standard (Check for short):

Symbols (Terminal No.)

Specified condition

Park/Neutral position switch (N1–6) or Starter relay (1) 

– Body ground

10 k

Ω

 or higher

(b)

Check the harness and the connector between the starter
relay and the body ground.
(1)

Remove the starter relay from the engine room R/B.

(2)

Check for resistance between the starter relay and
the body ground.

Standard (Check for open):

Symbols (Terminal No.)

Specified condition

Starter relay (2) – Body ground

Below 1 

Ω

NG

Repair or replace harness or connector.

OK