TOYOTA LAND CRUISER 1986 Factory Repair Manual

DI-302
- DIAGNOSTICSENGINE
495 Author
: Date
:
2004 LAND CRUISER (RM1071U)
DTC P2102 Throttle Actuator Control Motor Circuit Low
DTC P2103 Throttle Actuator Control Motor Circuit High
CIRCUIT DESCRIPTION
The throttle motor is operated by the ECM and it opens and closes the throttle valve.
The opening angle of the throttle valve is detected by the throttle position sensor which is mounted on the
throttle body. The throttle position sensor provides feedback to the ECM. This feedback allows the ECM to
control the throttle motor and monitor the throttle opening angle as the ECM responds to driver inputs.
HINT:
This Electrical Throttle Control System (ETCS) does not use a throttle cable.
DTC No.DTC Detection ConditionTrouble Area
P2102
Conditions (a) and (b) continue for 2.0 seconds:
(a) Throttle control motor output duty 80 % or more
(b) Throttle control motor current 0.5 A or less
Open in throttle control motor and sensor circuit

Throttle control motor and sensor

ECM
P2103
Either of following conditions is met.
(a) Throttle control motor current 10 A or more (0.1 sec)
(b) Throttle control motor current 7 A or more (0.6 sec.)

Short in throttle control motor and sensor circuit

Throttle control motor and sensor

Throttle valve

Throttle body

ECM
MONITOR DESCRIPTION
The ECM monitors the current through the electronic throttle motor and detects malfunctions or open circuit
in the throttle motor based on the voltage of the current. When the current deviates from the standard, the
ECM concludes that there is a fault in the throttle motor.
Or, if the throttle valve is not functioning properly (for example, stuck ON) the ECM concludes that there is
a fault and turns on the MIL and a DTC is set.
Example:
When the current is more than 10 A. Or the current is less than 0.5 A when the motor driving duty ratio is
exceeding 80%. The ECM concludes that the current is out of range, turns on the MIL and a DTC is set.
FAIL SAFE
If the ETCS (Electronic Throttle Control System) has a malfunction, the ECM cuts off current to the throttle
control motor. The throttle control valve returns to a predetermined opening angle (approximately 16°) by
the force of the return spring. The ECM then adjusts the engine output by controlling the fuel infection (inter-
mittent fuel-cut) and ignition timing in accordance with the accelerator pedal opening angle to enable the
vehicle to continue at a minimum speed.
If the accelerator pedal is depressed firmly and slowly, the vehicle can be driven slowly.
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.
DIC2O-01

- DIAGNOSTICSENGINE
DI-303
496 Author
: Date
:
2004 LAND CRUISER (RM1071U)
MONITOR STRATEGY
RltdDTC
P2102Throttle actuator control motor current
(Low current)
Related DTCs
P2103Throttle actuator control motor current
(High current)
Required sensors/componentsThrottle actuator motor
Frequency of operationContinuous
Duration2 sec.
MIL operationP2102: Immediate
P2103: 1 driving cycle
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever the follow-
ing DTCs are not presentSee ºList of disable a monitorº (on page DI-3)
P2102:
Throttle motorON
Duty-cycle ratio to open throttle actuator80%-
Throttle actuator power supply8 V-
Current motor current - Motor current at
0.016 sec. before-0.2 A
P2103:
Throttle motorON
Either of the following conditions is met:A or B
A. Throttle actuator power supply8 V-
B. Throttle actuator powerON
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
P2102:
Throttle motor currentLess than 0.5 A (when motor drive duty 80% or more)
P2103:
Throttle motor currentMore than 10 A (0.1 sec.)
More than 7 A (0.6 sec.)
WIRING DIAGRAM
Refer to DTC P0120 on page DI-84.

A21034
T16
Component Side:
M+M- Throttle Control Motor and Sensor
DI-304
- DIAGNOSTICSENGINE
497 Author
: Date
:
2004 LAND CRUISER (RM1071U)
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help deter-
mine 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 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:
Tester ConnectionSpecified Condition
M+ (T16-2) - M- (T16-1)0.3 to100 W (20°C (68°F))
NG Replace throttle body (See page SF-36).
OK

A21022
T16
M+ M-
Wire Harness Side:
Throttle Control Motor and Sensor
A21028
E7
M+M-
ECM Connector
- DIAGNOSTICSENGINE
DI-305
498 Author
: Date
:
2004 LAND CRUISER (RM1071U)
2 Check for open and short in harness and connector between throttle control mo-
tor and ECM.
PREPARATION:
(a) Disconnect the T16 throttle control motor and sensor con-
nector.
(b) Disconnect the E7 ECM connector.
CHECK:
Measure the resistance between the wire harness side connec-
tors.
OK:
Tester ConnectionSpecified Condition
M+ (T16-2) - M+ (E7-3)Below 1 W
M- (T16-1) - M- (E7-2)Below 1 W
M+ (T16-2) or M+ (E7-3) -
Body ground10 kW or higher
M- (T16-1) or M- (E7-2) -
Body ground10 kW or higher
NG Repair or replace harness or connector.
OK
3 Visually check throttle valve.
CHECK:
Check between the throttle valve and the housing for foreign objects.
Also, check if the valve can open and close smoothly.
NG Remove foreign object and clean throttle body.
OK
Replace ECM (See page SF-60).

DI-306
- DIAGNOSTICSENGINE
499 Author
: Date
:
2004 LAND CRUISER (RM1071U)
DTC P2111 Throttle Actuator Control System
-Stuck Open
DTC P2112 Throttle Actuator Control System
-Stuck Closed
CIRCUIT DESCRIPTION
The throttle motor is operated by the ECM and it opens and closes the throttle valve using gears. The open-
ing angle of the throttle valve is detected by the throttle position sensor, which is mounted on the throttle body.
The throttle position sensor provides feedback to the ECM to control the throttle motor and set the throttle
valve angle in response to driver input.
HINT:
This Electrical Throttle Control System (ETCS) does not use a throttle cable.
DTC No.DTC Detection ConditionTrouble Area
P2111Throttle motor locked during ECM order to close.
Throttle control motor and sensor circuit

Throttle control motor and sensor
P2112Throttle motor locked during ECM order to open.
Throttle control motor and sensor

Throttle body

Throttle valve
MONITOR DESCRIPTION
The ECM concludes that there is a malfunction of the ETCS (Electronic Throttle Control System) when the
throttle valve remains at a fixed angle despite high drive current from the ECM. The ECM will turn on the MIL
and a DTC is set.
FAIL SAFE
If the ETCS (Electronic Throttle Control System) has a malfunction, the ECM cuts off current to the throttle
control motor. The throttle control valve returns to a predetermined opening angle (approximately 16°) by
the force of the return spring. The ECM then adjusts the engine output by controlling the fuel infection (inter-
mittent fuel-cut) and ignition timing in accordance with the accelerator pedal opening angle to enable the
vehicle to continue at a minimum speed.
If the accelerator pedal is depressed firmly and slowly, the vehicle can be driven slowly.
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.
DIC2P-01

- DIAGNOSTICSENGINE
DI-307
500 Author
: Date
:
2004 LAND CRUISER (RM1071U)
MONITOR STRATEGY
RltdDTCP2111Throttle motor actuator lock (Open)Related DTCsP2112Throttle motor actuator lock (Closed)
Rid / tMain sensors/componentsThrottle actuator motorRequired sensors/componentsRelated sensors/componentsThrottle position sensor
Frequency of operationContinuous
Duration0.5 sec.
MIL operationImmediate
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever the follow-
ing DTCs are not presentSee ºList of disable a monitorº (on page DI-3)
P2111:
Throttle motor current2 A-
Throttle motor duty to close side80%-
P2112:
Throttle motor current2 A-
Throttle motor duty to open side80%-
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
|Current throttle position sensor voltage at this time - throttle
position sensor voltage 0.016 sec. earlier|Less than 0.1 V when throttle motor open (or close) duty 80% or more
WIRING DIAGRAM
Refer to DTC P0120 on page DI-84.
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help deter-
mine 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.

A21034
T16
Component Side:
M+M- Throttle Control Motor and Sensor
DI-308
- DIAGNOSTICSENGINE
501 Author
: Date
:
2004 LAND CRUISER (RM1071U)
1 Visually check throttle valve.
PREPARATION:
Remove the intake air connector.
CHECK:
Check whether or not a foreign matter is caught between the throttle valve and housing. Also, if the valve
can open and close smoothly.
NG Remove foreign matter and clean throttle body.
OK
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:
Tester ConnectionSpecified Condition
M+ (T16-2) - M- (T16-1)0.3 to100 W (20°C (68°F))
NG Replace throttle body (See page SF-36).
OK

A21022
T16
M+ M-
Wire Harness Side:
Throttle Control Motor and Sensor
A21028
E7
M+M-
ECM Connector
- DIAGNOSTICSENGINE
DI-309
502 Author
: Date
:
2004 LAND CRUISER (RM1071U)
3 Check for open and short in harness and connector between ECM and throttle
control motor.
PREPARATION:
(a) Disconnect the T16 throttle control motor and sensor con-
nector.
(b) Disconnect the E7 ECM connector.
CHECK:
Measure the resistance between the wire harness side connec-
tors.
OK:
Tester ConnectionSpecified Condition
M+ (T16-2) - M+ (E7-3)Below 1 W
M- (T16-1) - M- (E7-2)Below 1 W
M+ (T16-2) or M+ (E7-3) -
Body ground10 kW or higher
M- (T16-1) or M- (E7-2) -
Body ground10 kW or higher
NG Repair or replace harness or connector.
OK
Check for intermittent problems
(See page DI-3).

A21430
From BatteryETCS Fuse
+BM
+M
-M
ME01ECM
Motor Control
Circuit Throttle Control Motor DI-310
- DIAGNOSTICSENGINE
503 Author
: Date
:
2004 LAND CRUISER (RM1071U)
DTC P2118 Throttle Actuator Control Motor Current
Range/Performance
CIRCUIT DESCRIPTION
The Electronic Throttle Control System (ETCS) has a dedicated power supply circuit. The voltage (+BM) is
monitored and when the voltage is low (less than 4V), the ECM concludes that the ETCS has a fault and
current to the throttle control motor is cut.
When the voltage becomes unstable, the ETCS itself becomes unstable. For this reason, when the voltage
is low, the current to the motor is cut. If repairs are made and the system has returned to normal, turn the
ignition switch to OFF. The ECM then allows current to flow to the motor and the motor can be restarted.
HINT:
This Electrical Throttle Control System (ETCS) does not use a throttle cable.
DTC No.DTC Detection ConditionTrouble Area
P2118Open in ETCS power source circuit

Open in ETCS power source circuit

ETCS fuse

ECM
MONITOR DESCRIPTION
The ECM monitors the battery supply voltage applied to the electronic throttle motor. When the power supply
voltage drops below the threshold, the ECM concludes that the power supply has an open circuit. A DTC
is set and the MIL is turned on.
DIC2Q-01

- DIAGNOSTICSENGINE
DI-31 1
504 Author
: Date
:
2004 LAND CRUISER (RM1071U)
FAIL SAFE
If the ETCS (Electronic Throttle Control System) has a malfunction, the ECM cuts off current to the throttle
control motor. The throttle control valve returns to a predetermined opening angle (approximately 16°) by
the force of the return spring. The ECM then adjusts the engine output by controlling the fuel infection (inter-
mittent fuel-cut) and ignition timing in accordance with the accelerator pedal opening angle to enable the
vehicle to continue at a minimum speed.
If the accelerator pedal is depressed firmly and slowly, the vehicle can be driven slowly.
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 DTCsP2118Throttle actuator motor power supply line range
check (Low voltage)
Required sensors/componentsThrottle actuator motor
Frequency of operationContinuous
Duration0.8 sec.
MIL operationImmediate
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever the follow-
ing DTCs are not presentSee ºList of disable a monitorº (on page DI-3)
Actuator powerON
Battery voltage8 V-
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Throttle actuator motor power supply voltageLess than 4 V
COMPONENT OPERATING RANGE
ParameterStandard Value
Throttle actuator motor power supply voltage9 to 14 V