2001 TOYOTA SEQUOIA ECU

A23548
ECM
E4
STAR ACCR
AM28
ED I18
Ignition SWB B
B±W 1C9
620
42 P
1
B±W
B 1
J2
J/C 1
17
B±O
2D
ALTE7 J38
1FGR
W4
ED2 IA1
S3 F10
Fusible
Link Block4
W±R
B±L
Battery 5B
ST 3A
1
StarterST Relay 5
B
12 3
Instrument Panel J/B
12
Engine Room J/B
2C
5 Sub J/B No. 4
P 3A 12A36
ACC CUT Relay
to Audio
J37J/C
C
GR
4 GR
N B±R
B±R
J/C BD
J51 J52B±R
STSW
E6 IG4B
Engine Room R/B No.2
2 B
2 2
2
2 2 B±RB±R RAD No.2
1C
1C
1C
1J 1J1J
1L
1E 3
5
W±L W±R
W±R
2C
2E1
3B±R
3
B1
B±W
W±B 6
A 1
2 3 58
3
J5
J/C 1
1W±B 128 B±R
W±RJ51 BE6 11
STA W±R
21
3
S2W±R4A
4B 19
9 Sub J/B No.4 GR
P1
Park/Neutral
Position SW
AM1ACC
AM2
ST2
ECU±B
SHORT PIN
B 7
B 2AM1
1
STA8
IA5
± DIAGNOSTICSENGINE
DI±299
493 Author: Date:
2005 SEQUOIA (RM1146U)
WIRING DIAGRAM

B17426
± DIAGNOSTICSENGINE
DI±333
527 Author: Date:
2005 SEQUOIA (RM1146U)
WIRING DIAGRAM
Refer to DTC P1441, P1444 and P2440 on page DI±314.
INSPECTION PROCEDURE
1 Check any other DTCs output (In addition to secondary air injection system
DTCs).
PREPARATION:
(a) Connect a hand±held tester to the DLC3.
(b) Turn the ignition switch to ON and turn the tester ON.
(c) Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.
CHECK:
(a) Read DTCs.
RESULT:
Display (DTC Output)Proceed To
ºP1442 and/or P1445º and P2441A
P1442 and/or P1445B
ºP1442 and/or P1445 and/or P2441º and other DTCsC
HINT:
If any DTCs other than P1441 and/or P1444 and P2440 are output, troubleshoot those DTCs first.
B Go to step 6.
C Go to DTC chart (See page DI±58).
A
2 Check vacuum hose between throttle body and VSV for air injection control.
CHECK:
(a) Check that the vacuum hoses between the throttle body
and VSV for air injection control are securely connected.
OK:
The vacuum hoses are securely connected.
CHECK:
(a) Check the vacuum hoses for blockage or damage.
OK:
The vacuum hoses are no blockages and damage.
NG Repair or replace vacuum hoses.
OK

B17436
A23671
Port APort B
Air
A23672
Port APort B
Battery Air
± DIAGNOSTICSENGINE
DI±335
529 Author: Date:
2005 SEQUOIA (RM1146U)
4 Check all air injection pipes and hoses of air injection system.
CHECK:
(a) Remove the intake manifold (see page EM±36).
(b) Check all pipes and hoses of the air injection system.
OK:
All the air injection pipes and hoses are securely con-
nected.
CHECK:
(a) Check all pipes and hoses of the air injection system for
blockage or damage.
OK:
The air injection system pipes and hoses have no
blockage or damage.
NG Repair or replace pipe or hose.
OK
5 Check air switching valve operation.
PREPARATION:
(a) Remove the intake manifold (see page EM±36).
(b) Remove the air switching valve.
CHECK:
Blow air into port A and check that air is not discharged from port
B.
OK:
Not discharged
CHECK:
(a) Apply battery positive across the terminals.
(b) Blow air into port A and check that air is discharged from
port B.
OK:
Discharged
NG Replace air switching valve and go to step 6.
OK

A23452
B17530
Port C
Port B Port A
Air
B17531
Port C
Port BPort A
Air
DI±338
± DIAGNOSTICSENGINE
532 Author: Date:
2005 SEQUOIA (RM1146U)
8 Check vacuum hose between air switching valve(s) No.2 and VSV for air injec-
tion control.
CHECK:
(a) Check that the vacuum hoses between the air switching
valve(s) No.2 and VSV for air injection control are secure-
ly connected.
OK:
The vacuum hose(s) are securely connected.
CHECK:
(a) Check the vacuum hoses for blockages and damage.
OK:
The vacuum hoses no blockages and damages.
NG Repair or replace vacuum hose.
OK
9 Check air switching valve No.2 operation.
PREPARATION:
Remove the air switching valve No.2.
CHECK:
Blow air into port B and check that air is not discharged from the
port C.
OK:
Not discharged from port C
CHECK:
Apply vacuum 30 kPa (225 mmHg) to port A, blow air into port
B and check that air is discharged from the port C.
OK:
Discharged from port C
NG Replace air switching valve No.2.
OK

A23451
B17516
AirA
B17517
AirA
± DIAGNOSTICSENGINE
DI±339
533 Author: Date:
2005 SEQUOIA (RM1146U)
10 Check air injection pipe between air switching valve No.2 and exhaust manifold.
CHECK:
(a) Check that the air injection pipe between the air switching
valve(s) No.2 and exhaust manifold is securely con-
nected.
OK:
The air injection pipe is securely connected.
CHECK:
(a) Check the air injection pipe for blockages and damage.
OK:
The air injection pipe have no blockages and damage.
NG Repair or replace air injection pipe.
OK
Check for intermittent problems
(See page DI±11).
11 Check VSV for air injection control.
PREPARATION:
Disconnect the 2 vacuum hoses.
CHECK:
Check that air does not flow from the port A as shown in the il-
lustration.
OK:
Not flow from port A
CHECK:
Apply battery positive across the terminals, check that air flows
from the port A.
OK:
Flow from port A
NG Replace VSV for air injection control.
OK

± DIAGNOSTICSENGINE
DI±353
547 Author: Date:
2005 SEQUOIA (RM1146U)
9 Replace air injection driver.
NEXT
10 Check whether DTC output recurs.
PREPARATION:
(a) Connect a hand±held tester to the DLC3.
(b) Turn the ignition switch to ON and turn the tester ON.
(c) Clear the DTCs (see page DI±43).
(d) Start the engine.
CHECK:
(a) Perform SYSTEM CHECK to operate the air injection system.
Select the following menu items: DIAGNOSIS/ENHANCED OBD II/SYSTEM CHECK/AIR INJ
CHECK/AUTOMATIC OPERATION
(b) After operating the secondary air injection system, confirm the pending codes of the secondary air in-
jection system by selecting the following menu items: DIAGNOSIS/ENHANCED OBD II/DTC INFO/
PENDING CODES.
OK:
DTC P1613 for the secondary air injection system is not output.
NG Go to DTC chart (See page DI±58).
OK
END

± DIAGNOSTICSENGINE
DI±379
573 Author: Date:
2005 SEQUOIA (RM1146U)
5 Check whether DTC output recurs (DTC P2120, P2122, P2123, P2125, P2127,
P2128 or P2138)
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Disconnect the battery terminals or remove the EFI No. 1 fuse and ETCS fuse (Clear DTCs).
(c) Start the engine.
(d) Drive the engine at idle for 15 seconds or more.
(e) On the hand±held tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC
INFO / PENDING CODES.
CHECK:
Read the DTC output.
RESULT:
Display (DTC Output)Proceed To
P2120, P2122, P2123,P2125, P2127, P2128 or P2138A
No outputB
B System is OK.
A
Replace ECM (See page SF±80).

A23662
40 mph (64 km/h)
Idling
IG SW OFF ECT:
75C (167F) or higher
Vehicle Speed
Warming up(d)(f)
10 minutes
or more(g)
10 seconds
or more4 seconds
or moreTime At Least 3 times
(h) (i)
(j) Accelerator Pedal
DepressedAccelerator Pedal
Released (Fuel±cut)
DI±390
± DIAGNOSTICSENGINE
584 Author: Date:
2005 SEQUOIA (RM1146U)
CONFIRMATION DRIVING PATTERN
HINT:
This confirmation driving pattern is used in steps 2, 4, 7, 17 and 21 of the following diagnostic troubleshooting
procedure when using a hand±held tester.
(a) Connect the hand±held tester to DLC3.
(b) Turn the ignition switch to ON and turn the tester ON.
(c) Clear DTCs (see page DI±43).
(d) Start the engine, and warm it up until the ECT reaches 75C (167F) or higher.
(e) On the hand±held tester, select the following menu items: DIAGNOSIS/ENHANCED OBD II/DATA
LIST/FC IDL.
(f) Drive the vehicle at 40 mph (64 km/h) or more for at least 10 minutes.
(g) Change the transmission to 2nd gear.
(h) Drive the vehicle at proper vehicle speed to perform fuel±cut operation.
HINT:
Fuel±cut is performed under following conditions met:

Accelerator pedal fully released.

Engine speed 2,500 rpm or more (fuel injection returns at 1,000 rpm).
(i) Accelerate the vehicle to 30 mph (48 km/h) or more by depressing the accelerator pedal for at least
10 seconds.
(j) Soon after performing step (8) above, release the accelerator pedal for at least 4 seconds without de-
pressing the brake pedal, in order to execute fuel±cut control.
(k) Stop the vehicle and allow the engine to idle for 10 seconds or more.
(l) Allow the vehicle to decelerate until the vehicle speed declines to less than 6 mph (10 km/h).
(m) Repeat steps from (8) through (10) above at least 3 times in one driving cycle.
HINT:
Completing all A/F sensor monitors are required to change the value in TEST RESULT.
CAUTION:
Strictly observe of posted speed limits, traffic laws, and road conditions when performing these
drive pattern.