Toyota FJ Cruiser (GSJ 10, 15 series). Instruction - part 43

1GR-FE ENGINE CONTROL SYSTEM  –  SFI SYSTEM

ES–127

ES

HINT:
TP#1 denotes THROTTLE POS #1, and TP#2 denotes 
THROTTLE POS#2.

B

A

(a) Disconnect the B14 throttle with motor body connector.
(b) Disconnect the B1 ECM connector.
(c) Check the resistance.

Standard Resistance (Check for open)

Standard Resistance (Check for short)

(d) Reconnect the throttle with motor body connector.
(e) Reconnect the ECM connector.

NG

OK

0.5 to 1.1 V

2.1 to 3.1 V

3.3 to 4.9 V

4.6 to 5.0 V

TP sensor circuit

normal

B

TP#1 (VTA1)

When Accelerator 

Pedal Released

TP#2 (VTA2)

When Accelerator 

Pedal Released

TP#1 (VTA1)

When Accelerator 

Pedal Depressed

TP#2 (VTA2)

When Accelerator 

Pedal Depressed

Trouble Areas

Proceed To

              Go to step 5

2

CHECK HARNESS AND CONNECTOR (THROTTLE POSITION SENSOR - ECM)

Wire Harness Side:

Front View

ECM Connector

B1

B14

Throttle with Motor Body Connector

E2

VC

VTA2

VTA

E2

VC

VTA2

VTA1

A116167E06

Tester Connections

Specified Conditions

VC (B14-5) - VC (B1-23)

Below 1 

Ω

VTA (B14-6) - VTA1 (B1-20)

VTA2 (B14-4) - VTA2 (B1-19)

E2 (B14-3) - E2 (B1-28)

Tester Connections

Specified Conditions

VC (B14-5) or VC (B1-23) - Body grouB14nd

10 k

Ω or higher

VTA (B14-6) or VTA1 (B1-20) - Body ground

VTA2 (B14-4) or VTA2 (B1-19) - Body ground

REPAIR OR REPLACE HARNESS OR 
CONNECTOR

ES–128

1GR-FE ENGINE CONTROL SYSTEM  –  SFI SYSTEM

ES

(a) Disconnect the B14 throttle with motor body connector.
(b) Turn the ignition switch ON.
(c) Measure the voltage between the terminals of the B1 

ECM connector.
Standard Voltage

(d) Reconnect the throttle with motor body connector.

NG

OK

Replace the throttle with motor body assembly (See page 

ES-

428

).

NEXT

(a) Connect an intelligent tester to the DLC3.
(b) Turn the ignition switch ON and turn the tester ON.
(c) Clear DTCs (See page 

ES-38

).

(d) Start the engine.
(e) Allow the engine to idle for 15 seconds or more.
(f)

Select the following menu items: DIAGNOSIS / 
ENHANCED OBD II / DTC INFO / CURRENT CODES.

(g) Read DTCs.

Result

B

3

INSPECT ECM (VC VOLTAGE)

B14

Front View

ECM Connector

B1

Throttle with Motor Body Connector

Wire Harness Side:

E2 (-)

VC (+)

A116168E04

Tester Connections

Specified Conditions

VC (B1-23) - E2 (B1-28)

4.5 to 5.5 V

REPLACE ECM (See page 

ES-446

)

4

REPLACE THROTTLE WITH MOTOR BODY ASSEMBLY

5

CHECK WHETHER DTC OUTPUT RECURS (THROTTLE POSITION SENSOR DTCS)

Display (DTC Output)

Proceed To

P0120, P0122, P0123, P0220, P0222, P0223 and/or P2135

A

No output

B

SYSTEM OK

1GR-FE ENGINE CONTROL SYSTEM  –  SFI SYSTEM

ES–129

ES

A

REPLACE ECM (See page 

ES-446

)

ES–130

1GR-FE ENGINE CONTROL SYSTEM  –  SFI SYSTEM

ES

HINT:
This DTC relates to the Throttle Position (TP) sensor.

DESCRIPTION

Refer to DTC P0120 (See page 

ES-117

).

MONITOR DESCRIPTION

The ECM uses the TP sensor to monitor the throttle valve opening angle.
This sensor transmits two signals: VTA1 and VTA2. VTA1 is used to detect the throttle opening angle and 
VTA2 is used to detect malfunctions in VTA1. The ECM performs several checks to confirm the proper 
operation of the TP sensor and VTA1.
For each throttle opening angle, a specific voltage difference is expected between the outputs of VTA1 
and VTA2. If the voltage output difference between the two signals deviates from the normal operating 
range, the ECM interprets this as a malfunction of the TP sensor. The ECM illuminates the MIL and sets 
the DTC.
If the malfunction is not repaired successfully, the DTC is set 2 seconds after the engine is next started.

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

DTC

P0121

Throttle / Pedal Position Sensor / Switch "A" 
Circuit Range / Performance Problem

DTC No.

DTC Detection Conditions

Trouble Areas

P0121

Difference between VTA1 and VTA2 voltages less than 0.8 V, or more 
than 1.6 V for 2 seconds (1 trip detection logic)

•

TP sensor (built into throttle body)

Related DTCs

P0121: TP sensor rationality

Required Sensors/Components (Main)

TP sensor

Required Sensors/Components (Related)

-

Frequency of Operation

Continuous

Duration

Within 2 seconds 

MIL Operation

Immediate

Sequence of Operation

None

Either of following conditions A or B is met

-

A. Ignition switch

ON

B. Electric throttle motor power

ON

TP sensor malfunction (P0120, P0122, P0123, P0220, P0222, P0223, 
P2135)

Not detected

Either of following conditions is met

-

"Difference of TP sensor voltage between VTA1 and VTA2 x 0.8"

Higher than 1.6 V

"Difference of TP sensor voltage between VTA1 and VTA2 x 0.8"

Lower than 0.8 V