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A21576
± DIAGNOSTICSENGINE
DI±23
217 Author: Date:
2005 SEQUOIA (RM1146U)
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DID7V±01
01 BANK 1 ± SENSOR 1O2 SENSOR TEST
02 BANK 1 ± SENSOR 2
03 BANK 2 ± SENSOR 1
04 BANK 2 ± SENSOR 2
A21190
O2S TEST RESULT Screen DI±24
± DIAGNOSTICSENGINE
218 Author: Date:
2005 SEQUOIA (RM1146U)
O2S TEST RESULT
INTRODUCTION
The O2S TEST RESULT refers to the results of the engine con-
trol module (ECM) when it monitors the oxygen sensor (O2S),
and it can be read using the hand±held tester or the generic
OBD II scan tool. Based on this, you can find the O2S's condi-
tions.
The ECM monitors the O2S in the various items. You can read
the monitor result (TEST DATA) of each monitor item using the
O2S TEST RESULT. However, the output value of the TEST
DATA is the latest ºsnapshotº value that is taken after monitor-
ing and therefore it is not dynamic.
In this repair manual, the description of the O2S TEST RESULT
(for O2S related DTCs) are written in a table.
This table consists of 5 items:
(1) TEST ID (a code applied to each TEST DATA)
(2) Description of TEST DATA
(3) Conversion Factor (When Conversion Factor has a
value written in the table, multiply the TEST DATA
value appearing on the scan tool by the Conversion
Factor value. The result will be the required value.)
(4) Unit
(5) Standard Value
If the TEST DATA value appearing on the scan tool is out of the
standard value, the O2S is malfunctioning. If it is within the stan-
dard value, the O2S is functioning normally. However, if the val-
ue is on the borderline of the standard value, the O2S may mal-
function very soon.
HOW TO READ O2S TEST RESULT USING HAND±HELD
TESTER
(a) Connect the hand±held tester to the DLC3.
(b) On the tester screen, select the following menus: DIAG-
NOSIS / CARB OBDII / O2S TEST RESULT. A list of the
O2S equipped on the vehicle will be displayed.
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LOW SW V . . . . . . 0.400 V
HIGH SW V . . . . . .0.550 V
MIN O2S V . . . . . . 0.035 V
MAX O2S V . . . . . 0.835 V
Time $81 . . . . . . . . . . . 17
Time $84 . . . . . . . . . . . 84
Time $85 . . . . . . . . . . . 79
A21191
TEST DATA Screen
± DIAGNOSTICSENGINE
DI±25
219 Author: Date:
2005 SEQUOIA (RM1146U)
(c) Select the desired O2S and press ENTER. The following
screen will appear.
(d) Press HELP and
simultaneously. More information will
appear.
(e) Example:
(1) The hand±held tester displays º17º as a value of the
ºTIME $81º (see the illustration on the left).
(2) Find the Conversion Factor value of ºTIME $81º in
the O2S TEST RESULT chart below. 0.3906 is spe-
cified for $81 in this chart.
(3) Multiply º17º in step (1) by 0.3906 (Conversion Fac-
tor) in the step (2).
17 x 0.3906 = 6.6 %
(4) If the answer is within the standard value, the ºTIME
$81º can be confirmed to be normal.
O2S TEST RESULT Chart
TEST IDDescription of TEST DATAConversion FactorUnitStandard Value
$81
Percentage of monitoring time
when the HO2S voltage is less
than 0.05V
Multiply 0.3906%Within 60 %
Page 220 of 4323
![TOYOTA SEQUOIA 2001 Service Repair Manual DID7W±01
MID
TIDScaling Test Result Minimum Test Limit Maximum Test Limit
$E1 $E8ECT sensor output when estimated
ECT reached to malfunction criteria Multiply by 0.1 [°C]
Malfunction criteria Maxim TOYOTA SEQUOIA 2001 Service Repair Manual DID7W±01
MID
TIDScaling Test Result Minimum Test Limit Maximum Test Limit
$E1 $E8ECT sensor output when estimated
ECT reached to malfunction criteria Multiply by 0.1 [°C]
Malfunction criteria Maxim](/manual-img/14/57465/w960_57465-219.png)
DID7W±01
MID
TIDScaling Test Result Minimum Test Limit Maximum Test Limit
$E1 $E8ECT sensor output when estimated
ECT reached to malfunction criteria Multiply by 0.1 [°C]
Malfunction criteria Maximum test limit
DI±26
± DIAGNOSTICSENGINE
220 Author: Date:
2005 SEQUOIA (RM1146U)
CHECKING MONITOR STATUS
1. OUTLINE
The monitor results and the test values can be checked with the OBD II scan tool.
The engine control module (ECM) monitors the emissions±related components as the thermostat, catalyst
converter and evaporative emissions (EVAP), and determines whether they are functioning normally or not.
When finished and monitoring, the ECM stores the monitor results and the test values.
The monitor result indicates whether the component is functioning normally or not. The test value is the value
that was used to determine the monitor result. If the test value is outside the test limit (malfunction criterion),
the ECM determines the component is malfunctioning. Some emissions±related components have multiple
test values to determine monitor result. If one of these test values is outside test limit, the ECM determines
the component is determine monitor result. If one of these test values is outside test limit, the ECM deter-
mines the components is malfunctioning.
2. DESCRIPTION
The test value and test limit information are described as shown in the following table. This information is
included under ºMONITOR RESULTº in the emissions±related DTC sections.
Thermostat:
MID (Monitor Identification Data) is assigned to each emissions±related component.
TID (Test Identification Data) is assigned to each test value.
Scaling is used to calculate the test value indicated on generic OBD II scan tools.
3. PROCEDURE (USING HAND±HELD TESTER)
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch and hand±held tester ON.
(c) Clear DTCs.
(d) Allow the vehicle to drive, in accordance with the applicable drive pattern described in the READINESS
MONITOR DRIVE PATTERN section (see page DI±27).
(e) Check the monitor result. Select the hand±held tester menus: DIAGNOSIS/ENHANCED OBDII/MON-
ITOR INFO/MONITOR STATUS. The monitor result appears after the component name.
AVAIL indicates the component has not been monitored yet.
COMPL indicates the component is functioning normally.
INCMPL indicates the component is malfunctioning.
(f) Check the test value(s). Select the hand±held tester menus: DIAGNOSIS/ENHANCED OBDII/MON-
ITOR INFO/TEST RESULT.
(g) Select the component and press ENTER. If the monitor result has been COMPL or INCMPL, the accu-
racy test value appears.
(h) Compare the test value with the test limits, MIN and MAX.
If the test value is outside of the test limit, the component is malfunctioning.
If the test value is on the borderline of the test limit, a malfunction is concealed in the component.
HINT:
The monitor result might on rare occasions be COMPL even if the malfunction indicator lamp (MIL) is illumi-
nated. This indicates the system malfunctioned on a previous driving cycle. This might be caused by an inter-
mittent problem.
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DICEL±02
± DIAGNOSTICSENGINE
DI±27
221 Author: Date:
2005 SEQUOIA (RM1146U)
READINESS MONITOR DRIVE PATTERN
1. PURPOSE OF THE READINESS TESTS
The On±Board Diagnostic (OBD II) system is designed to monitor the performance of emission±re-
lated components and report any detected abnormalities in the form of Diagnostic Trouble Codes
(DTCs). Since the various components need to be monitored during different driving conditions, the
OBD II system is designed to run separate monitoring programs called Readiness Monitors. Many
state Inspection and Maintenance (I/M) programs require that vehicles complete their Readiness Mon-
itors prior to beginning an emission test.
The current status of the Readiness Monitors can be seen by using the hand±held tester with version
9.0 software (or newer), or a generic OBD II Scan tool.
To view the Readiness Monitor status using the hand±held tester, select ºMonitor Statusº from the En-
hanced OBD II Menu.
A status of ºcompleteº indicates that the necessary conditions have been met to run the performance
tests for the related Readiness Monitor.
The Readiness Monitor will be reset to ºincompleteº if:
ECM has lost power (battery or fuse).
DTCs have been cleared.
The conditions for running the Readiness Monitor have not been met.
In the event that any Readiness Monitor shows ºincomplete,º follow the appropriate Readiness Monitor
Drive Pattern to activate the monitor and change the readiness status to ºcomplete.º
CAUTION:
Strictly observe the posted speed limits, traffic laws, and road conditions when performing these
drive patterns.
NOTICE:
These drive patterns represent the fastest method to satisfy all necessary conditions which allow
the specific readiness monitor to complete.
In the event that the drive pattern must be interrupted (possibly due to traffic conditions or other fac-
tors) the drive pattern can be resumed, and in most cases, the readiness monitor will still set to ºcom-
pleteº.
To ensure rapid completion of readiness monitors, avoid sudden changes in vehicle load and speed
(driving up and down hills and/or sudden acceleration).
Contents:
TITLESTEP(s)
CATALYST MONITOR2
EVAP MONITOR3, 4
AIR±FUEL RATIO (A/F) AND OXYGEN SENSOR (O2S) MONITOR5
OXYGEN SENOSR HEATER MONITOR6
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A23510
Vehicle Speed
(64 km/h and 113 km/h)Between
40 mph and 70 mph
Idling
Ignition Switch OFF
10 minutes
Time Warm up
(Note: Even when vehicle stops during driving pattern, test can be resumed)NOTICE:
This test will not be completed
if the vehicle is driven under
absolute constant speed
condition such as with cruise
control activated. (6)
(5) DI±28
± DIAGNOSTICSENGINE
222 Author: Date:
2005 SEQUOIA (RM1146U)
2. CATALYST MONITOR (ACTIVE AIR±FUEL RATIO CONTROL TYPE)
(a) Preconditions
The monitor will not run unless:
The MIL is OFF
(b) Drive Pattern
(1) Connect a hand±held tester or OBD II scan tool to the DLC3.
(2) Turn the ignition switch to ON.
(3) Turn the tester or scan tool ON.
(4) Clear DTCs (where set) (see page DI±43).
(5) Start the engine and warm it up.
(6) Drive the vehicle at between 40 mph and 70 mph (64 km/h and 113 km/h) for at least 10 minutes.
(c) Monitor Status
(1) Check the Readiness Monitor status displayed on the tester or scan tool.
(2) If the status does not switch to COMPL (complete), extend the driving time.
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A18910
Idling
Ignition OFF
Warmed up Soak 15 to 50 min.
(When the readiness code or diagnostic code
is set, this test is completed.) 3,000 rpm
10 sec.
± DIAGNOSTICSENGINE
DI±29
223 Author: Date:
2005 SEQUOIA (RM1146U)
3. EVAP MONITOR (VACUUM PRESSURE MONITOR)
NOTICE:
A cold soak must be performed prior to conducting the drive pattern to complete the Internal Pres-
sure Readiness Monitor.
(a) Cold Soak Preconditions
The monitor will not run unless:
MIL is OFF
Fuel level is approximately 1/2 to 3/4
Altitude is 7,800 feet (2,400 m) or less
(b) Cold Soak Procedure
Let the vehicle cold soak for 8 hours or until the difference between IAT and ECT becomes less than
7°C (13°F)
HINT:
Examples:
Scenario 1
ECT = 24°C (75°F)
IAT = 16°C (60°F)
Difference between ECT and IAT is 8°C (15°F)
" The monitor will not run because difference between ECT and IAT is greater than 7°C (13°F)
Scenario 2
ECT = 21°C (70°F)
IAT = 20°C (68°F)
Difference between ECT and IAT is 1°C (2°F)
" The monitor will run because difference between ECT and IAT is less than 7°C (13°F)
4. EVAP MONITOR (VACUUM PRESSURE MONITOR) (CONTINUED)
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DI±30
± DIAGNOSTICSENGINE
224 Author: Date:
2005 SEQUOIA (RM1146U)
(a) Preconditions
The monitor will not run unless:
MIL is OFF
Fuel level is approximately 1/2 to 3/4
Altitude is 7,800 feet (2,400 m) or less
Engine Coolant Temperature (ECT) is between 4.4°C and 35°C (40°F and 95°F)
Intake Air Temperature (IAT) is between 4.4°C and 35°C (40°F and 95°F)
Cold Soak Procedure has been completed
Before starting the engine, the difference between ECT and IAT must be less than 7°C (13°F)
HINT:
Examples:
Scenario 1
ECT = 24°C (75°F)
IAT = 16°C (60°F)
Difference between ECT and IAT is 8°C (15°F)
" The monitor will not run because difference between ECT and IAT is higher than 7°C (13°F)
Scenario 2
ECT = 21°C (70°F)
IAT = 20°C (68°F)
Difference between ECT and IAT is 1°C (2°F)
" The monitor will run because difference between ECT and IAT is less than 7°C (13°F)
The readiness test can be completed in cold ambient conditions (less than 40°F / 4.4°C) and/or at
high altitudes (more than 7,800 feet / 2,400 m) if the drive pattern is repeated a second time after cycl-
ing the ignition off.
(b) Drive Pattern
(1) Connect the OBD II scan tool to DLC3 to check monitor status and preconditions (refer to (a)).
(2) Release pressure in fuel tank by removing the fuel tank cap and then reinstall it.
(3) Start the engine and allow it to idle until ECT becomes 75°C (167°F) or higher.
(4) Run the engine at 3,000 rpm for approximately 10 seconds.
(5) Allow the engine to idle with the A/C ON (to create slight load) for 15 to 50 minutes.
NOTICE:
If the vehicle is not equipped with A/C, put a slight load on the engine by doing the following :
Securely set the parking brake.
Block the drive wheels with wheel chocks.
Allow the vehicle to idle in drive for 15 to 50 minutes.