2001 TOYOTA SEQUOIA Page 18

A21034
T14
Component Side:
M+M± Throttle Control Motor and Sensor
± DIAGNOSTICSENGINE
DI±369
563 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check throttle control motor.
PREPARATION:
Disconnect the throttle control motor and sensor connector.
CHECK:
Measure the resistance between terminals of the throttle con-
trol motor.
OK:
Standard:
Tester ConnectionSpecified Condition
M+ (T14±2) ± M± (T14±1)0.3 to100 W (20°C (68°F))
NG Replace throttle body (See page SF±42).
OK
3 Replace ECM and check DTC (Check if DTC outputs reoccur).
PREPARATION:
(a) Replace ECM.
(b) Clear the DTC (See page DI±43).
(c) Start and warm up the engine.
(d) Run the engine at idle for 15 seconds or more.
CHECK:
Read the DTC using the hand±held tester (See page DI±43).
OK:
No DTC output.
OK System is normal.
NG
Replace throttle body.

± DIAGNOSTICSENGINE
DI±373
567 Author: Date:
2005 SEQUOIA (RM1146U)
MONITOR STRATEGY
P2120Accelerator position sensor 1 (VPA) range check
(Fluttering)
P2122Accelerator position sensor 1 (VPA) range check
(Low voltage)
P2123Accelerator position sensor 1 (VPA) range check
(High voltage)
Related DTCsP2125Accelerator position sensor 2 (VPA2) range
check (Fluttering)
P2127Accelerator position sensor 2 (VPA2) range
check (Low voltage)
P2128Accelerator position sensor 2 (VPA2) range
check (High voltage)
P2138Accelerator position sensor correlation range
check
Required sensors/componentsAccelerator position sensor
Frequency of operationContinuous
Duration2 sec.
MIL operationImmediate
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever these
DTCs are not presentSee page DI±18
Ignition switchON
Throttle control motor powerON

B17448
EPA (±)VCPA (+)
EPA2 (±)
VCP2 (+) Accelerator Pedal
Position Sensor
Connector
E4
A37
DI±378
± DIAGNOSTICSENGINE
572 Author: Date:
2005 SEQUOIA (RM1146U)
3 Check voltage between terminals VCPA and EPA, and VCP2 and EPA2 of ECM
terminals.
PREPARATION:
(a) Turn the ignition switch ON.
(b) Disconnect the A37 accelerator pedal position sensor
connector.
CHECK:
Measure the voltage between the specified terminals of the E4
ECM connector.
OK:
Standard:
Tester ConnectionSpecified Condition
VCPA (E4±26) ± EPA (E4±20)4.5 to 5.5 V
VCP2 (E4±27) ± EPA2 (E4±21)4.5 to 5.5 V
NG Replace ECM (See page SF±80).
OK
4 Replace accelerator pedal assembly (See page SF±78).
Go

± DIAGNOSTICSENGINE
DI±379
573 Author: Date:
2005 SEQUOIA (RM1146U)
5 Check whether DTC output recurs (DTC P2120, P2122, P2123, P2125, P2127,
P2128 or P2138)
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Disconnect the battery terminals or remove the EFI No. 1 fuse and ETCS fuse (Clear DTCs).
(c) Start the engine.
(d) Drive the engine at idle for 15 seconds or more.
(e) On the hand±held tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC
INFO / PENDING CODES.
CHECK:
Read the DTC output.
RESULT:
Display (DTC Output)Proceed To
P2120, P2122, P2123,P2125, P2127, P2128 or P2138A
No outputB
B System is OK.
A
Replace ECM (See page SF±80).

DI±380
± DIAGNOSTICSENGINE
574 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P2121 Throttle/Pedal Position Sensor/Switch ºDº
Circuit Range/Performance
HINT:
This is repair procedure for the ºaccelerator pedal position sensorº.
CIRCUIT DESCRIPTION
Refer to DTC P2120 on page DI±370.
DTC No.DTC Detecting ConditionTrouble Area
P2121
Conditions (a) and (b) continue for 0.5 seconds:
(a) Difference between VPA and VPA2 exceeds the threshold
(b) IDL is OFF
Accelerator pedal position sensor circuit

Accelerator pedal position sensor

ECM
MONITOR DESCRIPTION
The accelerator pedal position sensor is mounted on the accelerator pedal bracket. The accelerator pedal
position sensor has 2 sensor elements/signal outputs: VPA1 and VPA2. VPA1 is used to detect the actual
accelerator pedal angle (used for engine control) and VPA2 is used to detect malfunctions in VPA1. When
the difference between the voltage outputs of VPA1 and VPA2 deviates from the standard, the ECM con-
cludes the accelerator pedal position sensor has a malfunction. The ECM turns on the MIL and a DTC is
set.
FAIL SAFE
The accelerator pedal position sensor has two (main and sub) sensor circuits. If a malfunction occurs in ei-
ther of the sensor circuits, the ECM detects the abnormal signal voltage difference between the two sensor
circuits and switches to limp mode. In limp mode, the remaining circuit is used to calculate the accelerator
pedal opening to allow the vehicle to continue driving.
If both circuits malfunction, the ECM regards the opening angle of the accelerator pedal to be fully closed.
In this case, the throttle valve will remain closed as if the engine is idling.
If a ºpassº condition is detected and then the ignition switch is turned OFF, the fail±safe operation will stop
and the system will return to normal condition.
MONITOR STRATEGY
Related DTCsP2121Accelerator position sensor (rationality)
Required sensors/componentsAccelerator position sensor
Frequency of operationContinuous
Duration0.5 sec.
MIL operationImmediate
Sequence of operationNone
DID8H±01

FI7052DepressedReleased
± DIAGNOSTICSENGINE
DI±381
575 Author: Date:
2005 SEQUOIA (RM1146U)
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever this DTC is
not presentSee page DI±18
Either of the following conditions is metCondition 1 or 2
1. Ignition switchON
2. Throttle control motor powerON
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Difference between VPA1 voltage (learned value) and VPA2
voltage (learned value)Less than 0.4 V, or more than 1.2 V
WIRING DIAGRAM
Refer to DTC P2120 on page DI±370.
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 read the voltage for accelerator pedal position
sensor data.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON and push the hand±held tes-
ter main switch ON.
(c) Enter the following menu: DIAGNOSIS / ENHANCED
OBD II / DATA LIST / ETCS / ACCEL POS #1 and ACCEL
POS #2.
CHECK:
Read the voltage for the accelerator pedal position sensor data.
OK:
Standard:
Accelerator pedalACCEL POS #1ACCEL POS #2
Released0.5 to 1.1 V1.2 to 2.0 V
Depressed2.6 to 4.5 V3.4 to 5.3 V
OK Replace ECM (See page SF±80).
NG

± DIAGNOSTICSENGINE
DI±387
581 Author: Date:
2005 SEQUOIA (RM1146U)
MONITOR STRATEGY
P2195A/F sensor (Bank 1) signal stuck leanP2195A/F sensor (Bank 1) current (high side)
P2196A/F sensor (Bank 1) signal stuck rich
RltdDTC
P2196A/F sensor (Bank 1) current (low side)Related DTCs
P2197A/F sensor (Bank 2) signal stuck leanP2197A/F sensor (Bank 2) current (high side)
P2198A/F sensor (Bank 2) signal stuck richP2198A/F sensor (Bank 2) current (low side)
Required sensors/componentsA/F sensor
Frequency of operationOnce per driving cycle
Duration15 sec.: A/F sensor signal stuck lean/rich
3 sec.: A/F sensor current (high/low side)
MIL operation2 driving cycles
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever these
DTCs are not presentSee page DI±18
P2195, P2197 (A/F sensor signal stuck lean):
Duration while all of following conditions
met2 sec.±
Rear HO2S voltage0.15 V±
Time after engine start30 sec.±
A/F sensor statusActivated
Fuel system statusClosed±loop
EngineRunning
P2196, P2198 (A/F sensor signal stuck rich):
Duration while all of following conditions
met2 sec.±
Rear HO2S voltage±0.6 V
Time after engine start30 sec.±
A/F sensor statusActivated
Fuel system statusClosed±loop
EngineRunning
P2195, P2197 (A/F sensor current (High side)):
Battery voltage11 V±
ECT75°C (167°F)±
Atmospheric pressure/760 mmHg0.75±
A/F sensor statusActivated
Continuous time of fuel±cut3 to 10 sec.
P2196, P2198 (A/F sensor current (Low side)):
Battery voltage11 V±
ECT75°C (167°F)±

DI±388
± DIAGNOSTICSENGINE
582 Author: Date:
2005 SEQUOIA (RM1146U) Atmospheric pressure/760 mmHg
0.75±
A/F sensor statusActivated
Continuous time of fuel±cut3 to 10 sec.
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
P2195, P2197 (A/F sensor signal stuck lean):
A/F sensor voltageMore than 3.8 V for 15 sec.
P2196, P2198 (A/F sensor signal stuck rich):
A/F sensor voltageLess than 2.8 V for 15 sec.
P2195, P2197 (A/F sensor current (High side)):
Duration of the following condition3 sec. or more
A/F sensor current3.6 mA or more
P2196, P2198 (A/F sensor current (Low side)):
Duration of the following condition3 sec. or more
A/F sensor currentLess than 1.4 mA
MONITOR RESULT
Refer to page DI±26 for detailed information.
The test value and test limit information are described as shown in the following table. Check the monitor
result and test values after performing the monitor drive pattern (refer to ºConfirmation Monitorº).

MID (Monitor Identification Data) is assigned to each emissions±related component.

TID (Test Identification Data) is assigned to each test value.
A/F sensor bank 1 sensor 1
MIDTIDScalingDescription of Test ValueMinimum Test LimitMaximum Test Limit
$01$91Multiply by 0.003906
(mA)A/F currentMinimum test limitMaximum test limit
A/F sensor bank 2 sensor 1
MIDTIDScalingDescription of Test ValueMinimum Test LimitMaximum Test Limit
$05$91Multiply by 0.003906
(mA)A/F currentMinimum test limitMaximum test limit