Page 456 of 4323

DI±254
± DIAGNOSTICSENGINE
448 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand-held tester. Freeze frame data records the engine conditions when
a malfunction 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.
1 Are there any other codes (besides DTC P0420 or P0430) being output?
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON and push the hand±held tester main switch ON.
(c) When using hand±held tester, enter the following menu: DIAGNOSIS / ENHANCED OBD II / DTC
INFO / CURRENT CODES.
CHECK:
Read the DTC using the hand±held tester.
RESULT:
Display (DTC Output)Proceed to
ºP0420 and/or P0430ºA
ºP0420 or P0430º and other DTCsB
HINT:
If any other codes besides ºP0420 and/or P0430º are output, perform the troubleshooting for those DTCs
first.
B Go to relevant DTC chart (See page DI±58).
A
2 Check A/F sensor (bank 1, 2 sensor 1).
(a) Connect the hand±held tester to the DLC3.
(b) Start the engine and turn the tester ON.
(c) Warm up the engine with the engine speed at 2,500 rpm for approximately 90 seconds.
(d) On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST /
A/F CONTROL.
(e) Perform the A/F CONTROL operation with the engine in an idling condition (press the RIGHT or LEFT
button to change the fuel injection volume).
(f) Monitor the voltage outputs of the A/F and HO2 sensors (AFS B1S1 and O2S B1S2) displayed on the
tester.
HINT:
The A/F CONTROL operation lowers the fuel injection volume by 12.5 % or increases the injection
volume by 25 %.
Each sensor reacts in accordance with increases and decreases in the fuel injection volume.
Page 470 of 4323

DI±268
± DIAGNOSTICSENGINE
462 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
NOTICE:
When a vehicle is brought into the workshop, leave it as it is. Do not change the vehicle condi-
tion. For example, do not tighten the fuel tank cap.
Do not disassemble the pump module.
A hand±held tester is required to conduct the following diagnostic troubleshooting procedure.
1 Confirm DTC and EVAP pressure.
PREPARATION:
(a) Connect a hand±held tester to the DLC3.
(b) Turn the ignition switch to ON (do not start the engine).
(c) Turn the tester ON.
CHECK:
(a) Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.
(b) Read DTCs.
(c) Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / VAPOR
PRESS.
(d) Read the EVAP (Evaporative Emission) pressure displayed on the tester.
RESULT:
Display (DTC Output)Test ResultsSuspected Trouble AreasProceed To
P0451'Pressure sensorC
P0452Less than 45 kpa (430 mmHg)
Wire harness/connector (ECM ± pressure
sensor)
Pressure sensor
Short in ECM circuit
A
P0453More than 120 kPa (900 mmHg)
Wire harness/connector (ECM ± pressure
sensor)
Pressure sensor
Open in ECM circuit
B
B Go to step 4.
C Go to EVAP inspection procedure
(See page DI±460).
A
Page 474 of 4323
DI±272
± DIAGNOSTICSENGINE
466 Author: Date:
2005 SEQUOIA (RM1146U)
7 Replace ECM (See page SF±80).
NEXT
8 Check whether DTC output recurs.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch to ON and turn the tester ON.
(c) Wait for at least 60 seconds.
CHECK:
(a) On the tester, select the following menu items: DIAGNOSIS/ENHANCED OBD II/DTC INFO/PEND-
ING CODES.
HINT:
If no pending DTC is displayed on the tester, the repair has been successfully completed.
NEXT
Completed
Page 482 of 4323

DI±280
± DIAGNOSTICSENGINE
474 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand-held tester. Freeze frame data records the engine conditions when
a malfunction 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.
1 Check operation of speedometer.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch to ON and push the hand±held tester main switch ON.
(c) Start the engine.
(d) When using hand±held tester, enter the following menu: DIAGNOSIS / ENHANCED OBD II / DATA
LIST / PRIMARY / VEHICLE SPD.
CHECK:
Read the mass air flow rate on the hand±held tester.
RESULT:
Vehicle speedProceed to
Vehicle speed remains 0 km/h (0 mph)A
Vehicle speed is lower than actual speedA
Vehicle speed is same as actual speedB
B Check for intermittent problems
(See page DI±11).
A
Page 488 of 4323
B17446
Brake Pedal
DepressedBrake Pedal
Released ON
() ()
ST1±(+)E4
E6
E1(±)
DI±286
± DIAGNOSTICSENGINE
480 Author: Date:
2005 SEQUOIA (RM1146U)
3 Check STP signal and ST1± voltage.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON.
(c) Select the item ºDIAGNOSIS / ENHANCED OBD II /
DATA LIST / ALL / STOP LIGHT SWº.
CHECK:
Read the signal displayed on the hand±held tester.
OK:
Standard:
Brake PedalSpecified Condition
DepressedSTP Signal ON
ReleasedSTP Signal OFF
CHECK:
Measure the voltage between the specified terminals of the E4
and E6 ECM connectors.
OK:
Standard:
Tester ConnectionBrake PedalSpecified Condition
ST1± (E4±12) ±
E1 (E6±1)DepressedBelow 1.5 V
ST1± (E4±12) ±
E1 (E6±1)Released7.5 to 14 V
OK Check for intermittent problems (See page
DI±11).
NG
Page 492 of 4323

DI±290
± DIAGNOSTICSENGINE
484 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
HINT:
When the throttle position is slightly opened (the accelerator pedal is slightly depressed) because a
floor carpet is overlapped on the accelerator pedal, or if the accelerator pedal is not fully released, etc.,
DTC P0505 will possibly be detected.
Read freeze frame data using the hand-held tester. Freeze frame data records the engine conditions
when a malfunction 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.
1 Are there any other codes (besides P0505) being output?
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON and push the hand±held tester main switch ON.
(c) When using hand±held tester, enter the following menu: DIAGNOSIS / ENHANCED OBD II / DTC
INFO / CURRENT CODES.
CHECK:
Read the DTC using the hand±held tester.
RESULT:
Display (DTC Output)Proceed to
P0505A
ºP0505º and other DTCsB
HINT:
If any other codes besides P0505 are output, perform the troubleshooting for those DTCs first.
B Go to relevant DTC chart (See page DI±58).
A
2 Check connection of PCV piping.
NG Repair or replace PCV piping.
OK
Page 495 of 4323
A05652A18100
Battery2DEFI No. 1
B±Y
E4ECM
BATT 73
2H 1
IA411
B±Y B
F10
Fusible Link
Block 4Engine Room J/B
5
B12
± DIAGNOSTICSENGINE
DI±293
487 Author: Date:
2005 SEQUOIA (RM1146U)
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand-held tester. Freeze frame data records the engine conditions when
a malfunction 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.
1 Check battery voltage.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch to ON.
(c) Select the item: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / BATTERY VOLTAGE.
CHECK:
Read the battery voltage on the hand±held tester
RESULT:
Battery voltageProceed to
0 VA
Except 0 VB
B Go to step 5.
A
Page 502 of 4323

DI±300
± DIAGNOSTICSENGINE
494 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand±held tester. Freeze frame data records the engine conditions when
a malfunction 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.
1 Connect hand±held tester, and check STA signal.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON, and push the hand±held tester main switch ON.
(c) When using hand±held tester, enter the following menu: DIAGNOSIS / ENHANCED OBD II / DATA
LIST / ALL / STARTER SIG.
CHECK:
Read the STA signal on the hand±held tester while the starter operates.
OK:
Standard:
Ignition Switch PositionONSTART
STARTER SIGOFFON
OK Go to step 5.
NG
2 Check park/neutral position switch (See page DI±576).
NG Replace park/neutral position switch.
Go to next step 5 after the replacement.
OK
3 Check ignition switch (See page BE±24).
NG Replace ignition switch.
Go the next step 5 after the replacement.
OK