TOYOTA SEQUOIA 2001 Service Repair Manual

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

B17412
E8
AIV1
AIV2
B17437
V14
VSV Connector V15
Wire Harness Side:
DI±340
± DIAGNOSTICSENGINE
534 Author: Date:
2005 SEQUOIA (RM1146U)
12 Check for open and short circuit in harness and connector between ECM and
VSV for air injection system control
PREPARATION:
(a) Remove the intake manifold (see page EM±36).
(b) Disconnect the E8 ECM connector.
(c) Disconnect the VSV for air injection system control con-
nector.
CHECK:
Measure the resistance between the VSV connector and ECM.
OK:
Standard:
Tester connectionSpecified condition
E8±27 (AIV1) ± V14±2Below 1 W
E8±26 (AIV1) ± V15±2Below 1 W
CHECK:
Measure the resistance between the VSV connector and body
ground.
OK:
Standard:
Tester connectionSpecified condition
E8±27 (AIV1) or V14±2 and Body
ground10 KW or higher
E8±26 (AIV1) or V15±2 and Body
ground10 KW or higher
NG Repair or replace harness or connector.
OK

B17444
Wire Harness Side:
Air Injection Driver Connector
A41
VV
B17440
A46
Air Switching Valve Connector Wire Harness Side:
B17440
A46
Air Switching Valve Connector Wire Harness Side:
± DIAGNOSTICSENGINE
DI±341
535 Author: Date:
2005 SEQUOIA (RM1146U)
13 Check for open and short in harness and connector between air injection driver
and air switching valve.
PREPARATION:
(a) Remove the intake manifold (see page EM±36).
(b) Disconnect the A41 air injection driver connector.
(c) Disconnect the A46 air switching valve connector.
CHECK:
Measure the resistance between the wire harness side connec-
tors.
OK:
Standard:
Tester ConnectionSpecified Condition
VV (A41±6) ± A46±1Below 1 W
VV (A41±6) or A46±1 ±
Body ground10 kW or higher
NG Repair or replace harness or connector and go
to step 6.
OK
14 Check for open in harness and connector between air switching valve and body
ground.
PREPARATION:
(a) Remove the intake manifold (see page EM±36).
(b) Disconnect the A46 air switching valve connector.
CHECK:
Measure the resistance between the wire harness side connec-
tors and body ground.
OK:
Standard:
Tester ConnectionSpecified Condition
A46±2 ± Body groundBelow 1 W
NG Repair or replace harness or connector and go
to step 6.
OK

B17444
Wire Harness Side:
Air Injection Driver Connector
A41
SIV
B17417
E4
AIRV
DI±342
± DIAGNOSTICSENGINE
536 Author: Date:
2005 SEQUOIA (RM1146U)
15 Check for open and short in harness and connector between air injection driver
and ECM.
PREPARATION:
(a) Disconnect the air injection driver connector.
(b) Disconnect the E4 ECM connector.
CHECK:
Measure the resistance between the wire harness side connec-
tors.
OK:
Standard:
Tester ConnectionSpecified Condition
SIV (A41±3) ± AIRV (E4±4)Below 1 W
SIV (A41±3) or AIRV (E4±4) ±
Body ground10 kW or higher
NG Repair or replace harness or connector and go
to step 6.
OK
Replace ECM (See page SF±80).

± DIAGNOSTICSENGINE
DI±343
537 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P1613 Air Injection System Air Injection Driver
CIRCUIT DESCRIPTION
Refer to DTC P0412 on page DI±234.
DTC No.DTC Detection ConditionTrouble Area
P1613
Either of the following condition (a) or (b) is met:
(a) All of the following conditions are met (1 trip detection logic):

Either the air pump or air switching valve does not operate.

Air injection driver outputs a normal signal (80% duty signal)
(b) All of the following conditions are met (1 trip detection logic):

Air injection driver outputs an abnormal duty signal (duty sig-
nal excluding 0, 20, 40, 60, 80, 100%)

Air injection driver (AID)

Open in air injection driver ground circuit
P1613
All of the following conditions are met (1 trip detection logic):
(a) Air injection system operates (Air pump ON and all ASV
ON)
(b) Air injection driver outputs an air pump malfunction signal
(0% duty signal)
Short in diagnostic information signal circuit (AID ± ECM)

Open or short in air pump and air switching valve command
signal circuit (AID ± ECM)

Air injection driver (AID)

Open in air injection driver ground circuit

ECM
P1613Air injection driver outputs an abnormal duty signal (100% duty
signal) (1 trip detection logic)

Open or short in AID power source circuit

Open in diagnostic information signal circuit (AID ± ECM)

Air injection driver (AID)

ECM
MONITOR DESCRIPTION
When the air injection system operation is required while the engine is warming up, the ECM transmits com-
mand signals to the Air Injection Driver (AID) to drive the air pump and air switching valve.
AID detects an open or short in the air pump and air switching valve circuit according to the terminal voltage
and sends a signal as diagnostic information to the ECM.
If the air injection system drive circuit or the AID itself has a malfunction, the AID sends a malfunction signal
(duty signal) as a diagnostic information signal to the ECM (when the system is normal, a system normal
signal is sent).
The ECM sets the DTC based on the diagnostic information from the AID.
Example:
(1) The duty ratio of the diagnostic information signal output from the AID is 0 or 100% (remains at
0 V or battery voltage).
(2) The duty ratio output from the AID is the ratio to output the impossible (excluding 0, 20, 40, 60,
80, 100%).
(3) The AID outputs the normal signal (normal duty signal: 80%) while the system is not operating.
DIDMX±01

DI±344
± DIAGNOSTICSENGINE
538 Author: Date:
2005 SEQUOIA (RM1146U)
MONITOR STRATEGY
Related DTCsP1613Secondary air injection system control module
range check
Required sensors/componentsAir injection driver
Frequency of operationContinuous
Duration3 sec.
MIL operationImmediate
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever this DTC is
not presentSee page DI±18
Case 1:
Battery voltage8 V±
Ignition switchON
StarterOFF
Case 2:
Either of following conditions is metCondition 1 or 2
1. Air pumpNot operating
2. Air switching valveNot operating
Battery voltage8 V±
Ignition switchON
StarterOFF
Case 3:
Air pumpOperating
Air switching valveOperating
Battery voltage8 V±
Ignition switchON
StarterOFF
Case 4:
Battery voltage8 V±
Ignition switchON
StarterOFF
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Case 1:
One of the following conditions is metCondition 1, 2, 3 or 4
1. Diagnostic signal duty ratio from air injection driver1 to 10 %
2. Diagnostic signal duty ratio from air injection driver30 %
3. Diagnostic signal duty ratio from air injection driver49 %
4. Diagnostic signal duty ratio from air injection driver91 to 99 %
Case 2:
Diagnostic signal duty ratio from air injection driver70 to 90 %

B17411
ECM Connector
E1AIDI
A16555
AIR INJ CHECK
AIR PUMP............................ON
EASV ............................OPEN
ASV1. .............................OPEN
ASV2...............................OPEN
A/F BANK1.......................19.05
A/F BANK2.......................19.05
PRESSURE....................17 kPa
PULSATION..............25.39 kPa
AI STATUS...........................OK
Remaining Time 05 sec.
Press [EXIT] to quit
± DIAGNOSTICSENGINE
DI±345
539 Author: Date:
2005 SEQUOIA (RM1146U) Case 3:
Diagnostic signal duty ratio from air injection driver0 %
Case 4:
Diagnostic signal duty ratio from air injection driver100 %
COMPONENT OPERATING RANGE
ParameterStandard Value
Diagnostic signal duty ratio from air injection driver
70 to 90% when secondary air injection system operating
and
0% when secondary air injection system not operating
WIRING DIAGRAM
Refer to DTC P0412 on page DI±234.
INSPECTION PROCEDURE
HINT:
The diagnostic information output from the AID can be confirmed by connecting an oscilloscope to the diag-
nostic information terminal of the AID. It narrows a trouble area search to read the waveform on the oscillo-
scope when performing the AI system intrusive operation function provided in the SYSTEM CHECK.
(a) Start the engine and warm it up.
(b) Turn the ignition switch to OFF.
(c) Connect a hand±held tester to the DLC3.
(d) Connect an oscilloscope probe to the AIDI terminal of the
ECM.
(e) Start the engine and turn the tester ON.
(f) On the tester, select the following menu items:
DIAGNOSIS / ENHANCED OBD II / SYSTEM CHECK /
AIR INJ SYSTEM.
(g) On the tester, select the following menu items:
DIAGNOSIS / ENHANCED OBD II / SYSTEM CHECK /
AIR INJ CHECK / MANUAL OPERATION / OPERATION
1 and 2.
HINT:
OPERATION 1: AP: OFF, EASV:CLOSE, ASV1:CLOSE,
ASV2:OFF
OPERATION 2: AP: ON, EASV:OPEN, ASV1:OPEN,
ASV2:OPEN

Example: 80% Duty Signal5 V/DIV.
GND
20 ms/DIV. DI±346
± DIAGNOSTICSENGINE
540 Author: Date:
2005 SEQUOIA (RM1146U)
(1) Monitor the voltage output of the AID (duty ratio sig-
nal).
Oscilloscope range:
ItemsContents
TerminalsCH1: AIDI ± E1
Equipment Settings5 V/Division, 20 to 40 ms/Division
ConditionsIdling
NOTICE:

This AIR INJECTION CHECK only allows technicians to operate the AI system for 5 seconds.
Furthermore, the check can be performed 4 times a trip. If the test is repeated, intervals of at
least 30 seconds are required between checks.
While the AI system operation using the hand±held tester is prohibited, the tester displays the
prohibition (WAIT or ERROR). If the ERROR (AI STATUS NG) is displayed on the tester, stop the
engine for 10 minutes and then try again.

Performing the AIR INJ CHECK over and over again may cause the damage in the secondary
air injection system. If necessary, put an interval of several minutes between tests to prevent
overheating the system.

A23464
AID Diagnostic Signal WaveformsECM
CommandsDTCs
Suspected Trouble Areas
(ECM Output)
100 % Duty ratio
+B
Almost Battery Voltage
GND
0 % Duty ratio
+B
Fixed at Low Voltage
GND
20 % Duty ratio
20 %
+B
GND
40 % Duty ratio
40 %
+B
GND
80 % Duty ratio
80 %
+B
GND
Excluding above
(excluding 0, 20, 40, 80, 100 % duty)
Air Pump: ON
Air Pump: OFF
ASV: ON
ASV: OFF
AI System: OFF
(Air pump OFF,
ASV OFF)
AI System: ON
(Air pump ON,
ASV ON)
P1613
P0418
P0418
P0412
P0412
P1613
P1613
Air Injection Control Driver (AID)
Open in AID+B circuit (AID power source)
Open or short in air pump or Air Switching Valve
AID
ECM
Open in air pump drive circuit (AID±Pump) ,Harness & connector (AID±Pump)
Air PumpAIDECM
Short between air pump drive circuit and body ground
AID
ECM
Harness & connector (AID±Pump)Air Pump
Open in ASV drive circuit (AID±ASV),Harness & connector (AID±ASV)
ASVAIDECM
Short between ASV drive circuit and body ground
Harness & connector (AID±ASV)
AID
ECM
ECM
Normal
AID
AID
or short between air pump drive circuit and +B
or short between ASV drive circuit and +B
'
'
ASV
±
AI System: OFF
(Air pump OFF,
ASV OFF) AI System: ON
(Air pump ON,
ASV ON)
Normal Any Air Injection
(AI) System op-
eration
P1613
Open in AID ground circuit
Short between +B circuit and diagnostic signal circuit
Short between diagnostic signal circuit and body
(ASV) command signal circuit (ECM±AID)
ground
Open in AID ground circuit
Open in diagnostic signal circuit
± DIAGNOSTICSENGINE
DI±347
541 Author: Date:
2005 SEQUOIA (RM1146U)

DI±348
± DIAGNOSTICSENGINE
542 Author: Date:
2005 SEQUOIA (RM1146U)
HINT:

Using the AIR INJ CHECK operation of the SYSTEM CHECK provided in the hand±held tester func-
tion, conditions for air±fuel ratio and pressure in the secondary air injection system passage can be
checked while the secondary air injection system operating. It helps technicians to troubleshoot the
system when it malfunctioning.

Read freeze frame data using a hand±held tester. Freeze frame data record the engine condition when
malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle
was moving or stationary, if the engine was warmed up or not, if the air±fuel ratio was lean or rich, and
other data, from the time the malfunction occurred.
1 Check any other DTCs output (In addition to 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
P1613A
P1613 and other DTCsB
HINT:
If any DTCs other than P1613 are output, troubleshoot those DTCs first.
B Go to DTC chart (See page DI±58).
A