The VVT camshaft drive gear has a sensor plate with 3 teeth on its outer circumference. When the gear rotates, changes occur in the air gaps between the sensor plate and MRE, which affects the magnetic field. As a result, the resistance of the MRE material fluctuates. The VVT sensor converts the gear rotation data to pulse signals, uses the pulse signals to determine the camshaft angle, and sends it to the ECM.

The crankshaft angle sensor plate has 34 teeth. The pickup coil generates 34 signals for each revolution. Based on a combination of the VVT signal and NE signal, the ECM detects the crankshaft angle. Then the ECM uses this data to control fuel injection time and injection timing. Also, based on the NE signal, the ECM detects the engine speed.

DTC Code	DTC Detection Condition	Trouble Area
P0340 P0345	When either condition below is met: The input voltage to the ECM remains below 0.3 V or higher than 4.7 V for 4 seconds when 2 or more seconds have elapsed after turning the ignition switch ON (1 trip detection logic). No VVT sensor signal is sent to the ECM during cranking (2 trip detection logic).	Open or short in VVT sensor circuit VVT sensor Camshaft timing gear assembly Jumped tooth of timing chain ECM
P0342 P0347	The output voltage of the VVT sensor is below 0.3 V for 4 seconds (1 trip detection logic).
P0343 P0348	The output voltage of the VVT sensor is higher than 4.7 V for 4 seconds (1 trip detection logic).

Reference: Inspection using an oscilloscope
HINT:
1. The correct waveform is as shown.
2. VV1+ and VV2+ stand for the VVT sensor signal, and NE+ stands for the CKP sensor signal.
Item Content
Terminal NE+ - NE- VV1+ - VV1- VV2+ - VV2-
Equipment Setting 5 V/DIV. 20 msec./DIV.
Condition Cranking or idling

Monitor description

If no signal is transmitted by the VVT sensor despite the engine running, or the rotations of the camshaft and the crankshaft are not synchronized, the ECM interprets this as a malfunction of the sensor.

Wiring diagram

Inspection procedure

HINT:

Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

1.CHECK VVT SENSOR (SENSOR POWER SOURCE)

Disconnect the VVT sensor connector. DTC P0340 P0342 P0343 P0345 P0347 P0348 Land Cruiser 1GR-FE

Disconnect the VVT sensor connector.

Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection Condition Specified Condition
C25-3 (VC) - Body ground Always 4.5 to 5.0 V
C26-3 (VC) - Body ground Always 4.5 to 5.0 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

2.CHECK HARNESS AND CONNECTOR (VVT SENSOR - ECM)

Disconnect the VVT sensor connector. DTC P0340 P0342 P0343 P0345 P0347 P0348 Land Cruiser 1GR-FE

Disconnect the VVT sensor connector.

Disconnect the ECM connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):

for LHD
Tester Connection	Condition	Specified Condition
C26-1 (VVR+) - C45-69 (VV1+)	Always	Below 1 ?
C26-2 (VVR-) - C45-92 (VV1-)	Always	Below 1 ?
C25-1 (VVL+) - C45-67 (VV2+)	Always	Below 1 ?
C25-2 (VVL-) - C45-90 (VV2-)	Always	Below 1 ?

for RHD
Tester Connection	Condition	Specified Condition
C26-1 (VVR+) - C46-69 (VV1+)	Always	Below 1 ?
C26-2 (VVR-) - C46-92 (VV1-)	Always	Below 1 ?
C25-1 (VVL+) - C46-67 (VV2+)	Always	Below 1 ?
C25-2 (VVL-) - C46-90 (VV2-)	Always	Below 1 ?

Standard Resistance (Check for Short):

for LHD
Tester Connection	Condition	Specified Condition
C26-1 (VVR+) or C45-69 (VV1+) - Body ground	Always	10 k? or higher
C26-2 (VVR-) or C45-92 (VV1-) - Body ground	Always	10 k? or higher
C25-1 (VVL+) or C45-67 (VV2+) - Body ground	Always	10 k? or higher
C25-2 (VVL-) or C45-90 (VV2-) - Body ground	Always	10 k? or higher

for RHD
Tester Connection	Condition	Specified Condition
C26-1 (VVR+) or C46-69 (VV1+) - Body ground	Always	10 k? or higher
C26-2 (VVR-) or C46-92 (VV1-) - Body ground	Always	10 k? or higher
C25-1 (VVL+) or C46-67 (VV2+) - Body ground	Always	10 k? or higher
C25-2 (VVL-) or C46-90 (VV2-) - Body ground	Always	10 k? or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.CHECK SENSOR INSTALLATION

Check the VVT sensor installation. DTC P0340 P0342 P0343 P0345 P0347 P0348 Land Cruiser 1GR-FE

Check the VVT sensor installation.

OK:

Sensor is installed correctly.

NG

SECURELY REINSTALL SENSOR

OK

4.CHECK VALVE TIMING

Remove the cylinder head cover. DTC P0340 P0342 P0343 P0345 P0347 P0348 Land Cruiser 1GR-FE

Remove the cylinder head cover.

Turn the crankshaft pulley, and align its groove with the timing mark "0" of the timing chain cover.

Check that the timing marks of the camshaft timing gears are aligned with the timing marks of the bearing cap as shown in the illustration.

If not, turn the crankshaft 1 revolution (360°), then align the marks as above.

OK:

Timing marks on camshaft timing gears are aligned as shown in the illustration.

NG

ADJUST VALVE TIMING

OK

5.CHECK CAMSHAFT TIMING GEAR ASSEMBLY (TEETH OF PLATE)

Check the teeth of the signal plate.

OK:

Sensor plate teeth do not have any cracks or deformation.

NG

REPLACE CAMSHAFT TIMING GEAR ASSEMBLY

OK

6.REPLACE VVT SENSOR

Replace the VVT sensor .

NEXT

7.CHECK WHETHER DTC OUTPUT RECURS

Connect the intelligent tester to the DLC3.

Turn the ignition switch to ON.

Turn the tester on.

Clear the DTCs .

Start the engine.

Enter the following menus: Powertrain / Engine and ECT / DTC.

Read the DTCs.

Result
Result Proceed to
No output A
P0340, P0342, P0343, P0345, P0347 or P0348 B
HINT:

If the engine does not start, replace the ECM.

Result
Result	Proceed to
No output	A
P0340, P0342, P0343, P0345, P0347 or P0348	B

B

REPLACE ECM

A

END

Item	Content
Terminal	NE+ - NE- VV1+ - VV1- VV2+ - VV2-
Equipment Setting	5 V/DIV. 20 msec./DIV.
Condition	Cranking or idling