Toyota Sequoia (2005). Manual - part 55

A21576

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DIAGNOSTICS

ENGINE

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217

DID7V–01

01  BANK  1  –  SENSOR  1

O2 SENSOR TEST

02  BANK  1  –  SENSOR  2
03  BANK  2  –  SENSOR  1
04  BANK  2  –  SENSOR  2

A21190

O2S TEST RESULT Screen

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DIAGNOSTICS

ENGINE

218

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 ”snapshot” 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.

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

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DIAGNOSTICS

ENGINE

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219

(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 ”17” as a value of the
”TIME $81” (see the illustration on the left).

(2)

Find the Conversion Factor value of ”TIME $81” in
the O2S TEST RESULT chart below. 0.3906 is spe-
cified for $81 in this chart.

(3)

Multiply ”17” 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 ”TIME
$81” can be confirmed to be normal.

O2S TEST RESULT Chart

TEST ID

Description of TEST DATA

Conversion Factor

Unit

Standard Value

$81

Percentage of monitoring time
when the HO2S voltage is less
than 0.05V

Multiply 0.3906

%

Within 60 %

DID7W–01

MID

TID

Scaling

Test Result

Minimum Test Limit

Maximum Test Limit

$E1

$E8

ECT sensor output when estimated
ECT reached to malfunction criteria

Multiply by 0.1 [

°

C]

Malfunction criteria

Maximum test limit

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DIAGNOSTICS

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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 ”MONITOR RESULT” 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.