Toyota Sequoia (2005). Manual - part 68

A07621

A09776

1

2

L–W

P–L

OC1+

OC1–

OC2+

OC2–

17

L–B

R–L

1

2

E6

C13
OCV (Bank 1)

C14
OCV (Bank 2)

ECM

16

15

14

E6

E6

E6

–

DIAGNOSTICS

ENGINE

DI–75

269

WIRING DIAGRAM

INSPECTION PROCEDURE

HINT:

If DTC P0010 displayed, check left bank OCV circuit.

If DTC P0020 displayed, check right bank OCV circuit.

Read freeze frame data using hand–held tester. Because freeze frame records the engine conditions
when the malfunction is detected. When troubleshooting, it is useful for determining whether the ve-
hicle was running or stopped, the engine was warmed up or not, the air–fuel ratio was lean or rich, etc.
at the time of the malfunction.

A31449

A23511

Valve

Battery –

Battery +

DI–76

–

DIAGNOSTICS

ENGINE

270

1

Check OCV circuit.

PREPARATION:
(a)

Connect the hand–held tester to the DLC3.

(b)

Start the engine and warm it up.

(c)

Turn the ignition switch to ON and turn the hand–held tester ON.

CHECK:
(a)

Select the item: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / VVT CTRL B1 or VVT CTRL B2.

(b)

Using the hand–held tester, operate the OCV and check the engine speed.

OK:

Standard:

Tester Operation

Specified Condition

OCV is OFF

Normal engine speed

OCV is ON

Rough idle or engine stall

OK

Check for intermittent problems 
(See page 

DI–11

).

NG

2

Check operation of OCV.

PREPARATION:
(a)

Start the engine and warmed it up.

(b)

Disconnect the OCV connector.

(c)

Apply battery positive voltage between the terminals of
the OCV.

CHECK:
Check the engine speed.
OK:

Rough idle or engine stalled.

NG

Replace OCV.

OK

A02397

OCV Signal Waveform

1 msec./Division

5 V/
Division

GND

(A)

(A)

(A)

B17414

ECM Connector

E6

OC1+

OC1–

OC2+

OC2–

E1

–

DIAGNOSTICS

ENGINE

DI–77

271

3

Check voltage between terminals OC1+ and OC1–, OC2+ and OC2– of ECM con-
nector.

CHECK:
(a)

Inspection using the oscilloscope.

(b)

During idling, check the waveform between the specified
terminals of the E6 ECM connector.

HINT:
The waveform frequency (A) is lengthened as the engine speed
becomes higher.
OK:

Standard:
The correct waveform is as shown.

NG

Replace ECM (See page 

SF–80

).

OK

A23673

Wire Harness Side

C13

OCV Connector

C14

B17414

ECM Connector

E6

OC1+

OC1–

OC2+

OC2–

E1

DI–78

–

DIAGNOSTICS

ENGINE

272

4

Check for open and short in harness and connector between OCV and ECM.

PREPARATION:
(a)

Disconnect the C13 or C14 OCV connector.

(b)

Disconnect the E6 ECM connector.

CHECK:
(a)

Check for resistance between the wire harness side con-
nectors.

OK:

Standard (Check for open):

Symbols (Terminal No.)

Specified condition

OCV (C14–1) – OC1+ (E6–17)

Below 1 

Ω

OCV (C14–2) – OC1– (E6–16)

Below 1 

Ω

OCV (C13–1) – OC2+ (E6–15)

Below 1 

Ω

OCV (C13–2) – OC2– (E6–14)

Below 1 

Ω

Standard (Check for short):

Symbols (Terminal No.)

Specified condition

OCV (C14–1) or OC1+ (E6–17) – E1 (E6–1)

10 k

Ω

 or higher

OCV (C14–1) or OC1– (E6–16) – E1 (E6–1)

10 k

Ω

 or higher

OCV (C13–1) or OC2+ (E6–15) – E1 (E6–1)

10 k

Ω

 or higher

OCV (C13–1) or OC2– (E6–14) – E1 (E6–1)

10 k

Ω

 or higher

NG

Repair or replace harness or connector.

OK

Check for intermittent problems 
(See page 

DI–11

).