check engine TOYOTA SEQUOIA 2001 Service Owner's Manual

DID7R±01
± DIAGNOSTICSENGINE
DI±11
205 Author: Date:
2005 SEQUOIA (RM1146U)
CHECK FOR INTERMITTENT PROBLEMS
HINT:
Hand±held tester only:
Inspect the vehicle's ECM using check mode. Intermittent problems are easier to detect with a hand±held
tester when the ECM is in check mode. In check mode, the ECM uses 1trip detection logic, which is more
sensitive to malfunctions than normal mode (default), which uses 2 trip detection logic.
(d) Clear DTCs (see page DI±43).
(e) Switch the ECM from normal mode to check mode using a hand±held tester (see page DI±44).
(f) Perform a simulation test (see page IN±24).
(g) Check and wiggle the harness(es), connector(s) and terminal(s) (see page IN±35).

DID7S±01
DI±12
± DIAGNOSTICSENGINE
206 Author: Date:
2005 SEQUOIA (RM1146U)
BASIC INSPECTION
When the malfunction is not confirmed in the DTC check, troubleshooting should be carried out in all the
possible circuits considered as causes of the problem. In many cases, by carrying out the basic engine check
shown in the following flowchart, the location causing the problem can be found quickly and efficiently. There-
fore, using this check is essential in the engine troubleshooting.
1 Is battery voltage 11 V or more when engine stopped?
NO Charge or replace battery.
YES
2 Is engine cranked?
NO Proceed to page ST±15 and continue to trouble-
shoot.
YES
3 Does engine start?
NO Go to step 6.
YES

± DIAGNOSTICSENGINE
DI±13
207 Author: Date:
2005 SEQUOIA (RM1146U)
4 Check air filter.
PREPARATION:
Remove the air filter.
CHECK:
Visual check that the air filter is not excessively dirty or oily.
NG Repair or replace
air filter.
OK
5 Check idle speed (See page EM±11).
NG Proceed to problem symptoms table on page
DI±33.
OK
6 Check fuel pressure (See page SF±7).
NG Proceed to page SF±7 and continue to trouble-
shoot.
OK
7 Check for spark (See page IG±1).
NG Proceed to page IG±1 and continue to trouble-
shoot.
OK
Proceed to problem symptoms table on page
DI±33.

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.

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.

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.

A23544
40 mph (64 km/h)
Idling
IG SW OFF ECT:
75C (167F) or higher
Vehicle Speed
Warming up(5)(6)
10 minutes
or more(7)
10 seconds
or more4 seconds
or moreTime At Least 3 times
(8) (9)
(10) Accelerator Pedal
DepressedAccelerator Pedal
Released (Fuel±cut)
± DIAGNOSTICSENGINE
DI±31
225 Author: Date:
2005 SEQUOIA (RM1146U)
5. AIR±FUEL RATIO (A/F) AND OXYGEN SENSOR (HO2) MONITOR (ACTIVE AIR±FUEL RATIO
CONTROL TYPE)
(a) Preconditions
The monitor will not run unless:

2 minutes or more have elapsed since the engine was started.

The Engine Coolant Temperature (ECT) is 75C (167F) or higher.

Air±fuel ratio feedback control is performed.

Fuel±cut control is performed for 8 seconds or more.
(b) Drive Pattern
(1) Connect the hand±held tester to DLC3.
(2) Turn the ignition switch to ON.
(3) Clear DTCs (see page DI±43).
(4) Start the engine, and warm it up until the ECT reaches 75C (167F) or higher.
(5) Drive the vehicle at 40 mph (64 km/h) or more for at least 10 minutes.
(6) Change the transmission to 2nd gear.
(7) Accelerate the vehicle to 30 mph (48 km/h) or more by depressing the accelerator pedal for at
least 10 seconds.
(8) Soon after performing step (8) above, release the accelerator pedal for at least 4 seconds without
depressing the brake pedal, in order to execute fuel±cut control.
(9) Stop the vehicle and allow the engine to idle for 10 seconds or more.
(10) Allow the vehicle to decelerate until the vehicle speed declines to less than 6 mph (10 km/h).
(11) Repeat steps from (8) through (10) above at least 3 times in one driving cycle.
(c) Monitor Status
(1) Check the Readiness Monitor status displayed on the tester.
(2) If the status does not switch to COMPL (complete), make sure that the preconditions have been
met, and then perform steps from (5) through (11) in Drive Pattern above.

A18915
Idling
Ignition OFF(40 km/h)25 mph
Over 2 minutes Over 500 seconds DI±32
± DIAGNOSTICSENGINE
226 Author: Date:
2005 SEQUOIA (RM1146U)
6. OXYGEN SENSOR HEATER MONITOR
(a) Preconditions
The monitor will not run unless:

MIL is OFF
(b) Drive Pattern
(1) Connect the OBD II scan tool to the DLC3 to check monitor status and preconditions (refer to
(a)).
(2) Start the engine and allow it to idle for 500 seconds or more.
(3) Drive the vehicle at 25 mph (40 km/h) or more for at least 2 minutes.
(4) Check the status of the readiness monitor on the scan tool display. If readiness status did not
switch to complete, ensure the preconditions are met, turn the ignition off and then repeat steps
(2) and (3).

DID7X±01
FI0534
D13872
Hand±Held Tester
DLC3
DI±40
± DIAGNOSTICSENGINE
234 Author: Date:
2005 SEQUOIA (RM1146U)
DIAGNOSIS SYSTEM
1. Description

When troubleshooting On±Board Diagnostic (OBD ll) ve-
hicles, the vehicle must be connected to the hand±held
tester. Various data output from the vehicle's ECM can
then be read.

OBD ll regulations require that the vehicle's on±board
computer illuminates the Malfunction Indicator Light (MIL)
on the instrument panel when the computer detects a
malfunction in: 1) the emission control system/compo-
nents, or 2) the powertrain control components (which af-
fect vehicle emissions), or 3) the computer. In addition,
the applicable Diagnostic Trouble Codes (DTCs) pre-
scribed by SAE J2012 are recorded in the ECM memory
(See page DI±58).
If the malfunction does not reoccur in 3 consecutive trips, the
MIL goes off automatically but the DTCs remain recorded in the
ECM memory.
To check the DTC, connect the hand±held tester or OBD II scan
tool to the Data Link Connector 3 (DLC3) of the vehicle. The
hand±held tester or OBD II scan tool also enables you to erase
the DTC and check the freeze frame data and various forms of
engine data (See the instruction manual for the hand±held tes-
ter). The DTC includes SAE controlled codes and manufacturer
controlled codes. SAE controlled codes must be set according
to the SAE, while manufacturer controlled codes can be set by
a manufacturer with certain restrictions (See the DTC chart on
page DI±58).
2. NORMAL MODE AND CHECK MODE
The diagnosis system operates in ºnormal modeº during normal
vehicle use. In ºnormal modeº, 2 trip detection logic* is used to
ensure accurate detection of malfunctions. A ºcheck modeº is
also available to technicians as an option. In ºcheck modeº, 1
trip detection logic is used for simulating malfunction symptoms
and increasing the system's ability to detect malfunctions, in-
cluding intermittent malfunctions (See page DI±11).
3. 2±TRIP DETECTION LOGIC
When a malfunction is first detected, the malfunction is tempo-
rarily stored in the ECM memory. This is known as 1st trip detec-
tion. If the ignition switch is turned OFF and then ON again, and
the same malfunction is detected again, the MIL will illuminate.
This is known as 2nd trip detection.

A04550
12 345678
11 12 13 14 15 16 910
DLC3
± DIAGNOSTICSENGINE
DI±41
235 Author: Date:
2005 SEQUOIA (RM1146U)

Freeze frame data:
The freeze frame data records the engine conditions (fuel
system, calculated load, engine coolant temperature, fuel
trim, engine speed, vehicle speed, etc.) when a malfunc-
tion is detected. When troubleshooting, freeze frame data
can help determine if the vehicle was running or stopped,
if the engine was warmed up or not, if the air±fuel ratio
was lean or rich, as well as other data from the time when
a malfunction occurred.
Priorities for troubleshooting:
When multiple DTCs occur, find out the order in which the DTCs
should be inspected by checking the component's DTC chart.
If no instructions are written in the DTC chart, check DTCs in the
following order of priority:
(a) DTCs other than fuel trim malfunction DTCs (P0171,
P0172, P0174 and P0175) and misfire DTCs (P0300 to
P0308).
(b) Fuel trim malfunction DTCs (P0171, P0172, P0174 and
P0175).
(c) Misfire DTCs (P0300 to P0308).
4. CHECK DLC3
The vehicle's ECM uses the ISO 9141±2 for communica-
tion protocol. The terminal arrangement of the DLC3 com-
plies with SAE J1962 and matches the ISO 9141±2 for-
mat.
SymbolTerminal DescriptionConditionSpecified Condition
SIL (7) ± SG (5)Bus º+º lineDuring transmissionPulse generation
CG (4) ± Body groundChassis groundAlwaysBelow 1 W
SG (5) ± Body groundSignal groundAlwaysBelow 1 W
BAT (16) ± Body groundBattery positiveAlways11 to 14 V
CANH (6) ± CANL (14)HIGH±level CAN bus lineIgnition switch OFF54 to 69 W
CANH (6) ± Battery positiveHIGH±level CAN bus lineIgnition switch OFF1 MW or higher
CANH (6) ± CG (4)HIGH±level CAN bus lineIgnition switch OFF1 kW or higher
CANL (14) ± Battery positiveLOW±level CAN bus lineIgnition switch OFF1 MW or higher
CANL (6) ± CG (4)LOW±level CAN bus lineIgnition switch OFF1 kW or higher
HINT:
Connect the cable of the hand±held tester to the DLC3, turn the
ignition switch ON and attempt to use the hand±held tester. If
the screen displays UNABLE TO CONNECT TO VEHICLE, a
problem exists in the vehicle side or the tester side.

If the communication is normal when the tool is connected
to another vehicle, inspect the DLC3 on the original ve-
hicle.