1Gr-Fe Engine Control. Dtc P0300 Random / Multiple Cylinder Misfire Detected

When the engine misfires, high concentrations of hydrocarbons (HC) enter the exhaust gas. Extremely high hydrocarbon concentration levels can cause increases in exhaust emission levels. High concentrations of hydrocarbons can also cause increases in the three-way catalytic converter temperature, which may cause damage to the three-way catalytic converter. To prevent these increases in emissions and to limit the possibility of thermal damage, the ECM monitors the misfire count. When the temperature of the three-way catalytic converter reaches the point of thermal degradation, the ECM blinks the MIL. To monitor misfires, the ECM uses both the VVT sensor and crankshaft position sensor. The VVT sensor is used to identify any misfiring cylinders and the crankshaft position sensor is used to measure variations in the crankshaft rotation speed. Misfires are counted when the crankshaft rotation speed variations exceed predetermined thresholds.
If the misfire count exceeds the threshold level and could cause emission deterioration, the ECM illuminates the MIL and stores a DTC.

DTC No.	DTC Detection Condition	Trouble Area
P0300	Simultaneous misfiring of several cylinders occurs and one of the following conditions is detected (2 trip detection logic): High temperature misfire occurs in three-way catalytic converter (MIL blinks when detect immediately). Emission deterioration misfire occurs (MIL illuminates).	Open or short in engine wire harness Connector connections Vacuum hose connections Ignition system Fuel injector assembly Fuel pressure Mass air flow meter sub-assembly Engine coolant temperature sensor Compression pressure Valve timing PCV valve and hose PCV hose connections Intake system ECM
P0301 P0302 P0303 P0304 P0305 P0306	Misfiring of specific cylinder occurs and one of the following conditions is detected (2 trip detection logic): High temperature misfire occurs in three-way catalytic converter (MIL blinks when detect immediately). Emission deterioration misfire occurs (MIL illuminates).

When DTCs for misfiring cylinders are randomly stored, but DTC P0300 is not stored, it indicates that misfires have been detected in different cylinders at different times. DTC P0300 is only stored when several misfiring cylinders are detected at the same time.

WIRING DIAGRAM

for Automatic Transmission

for Manual Transmission

CONFIRMATION DRIVING PATTERN

Connect the GTS to the DLC3.
Turn the engine switch on (IG).
Turn the GTS on.
Record the DTC(s) and freeze frame data.
Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Cylinder #1 (to #6) Misfire Count.
Read the misfire counts of each cylinder (Cylinder #1 (to #6) Misfire Count) with the engine idling. If any misfire count is displayed, skip the following confirmation driving pattern.
Drive the vehicle several times with the conditions, such as engine speed and engine load, as shown in Misfire RPM and Misfire Load in the Data List.

HINT:
In order to store misfire DTCs, it is necessary to operate the vehicle for the period of time shown in the table below, using the Misfire RPM and Misfire Load in the Data List.

Engine Speed
Duration
Idling
8 minutes or more
1000
4.5 minutes or more
2000
2.5 minutes or more
3000
1.5 minutes or more
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.
Check whether misfires have occurred by checking pending DTCs and freeze frame data.
HINT:
Do not turn the engine switch off until the stored DTCs and freeze frame data have been recorded. When the ECM returns to normal mode (default), the stored DTCs, freeze frame data and other data will be cleared.
Record the pending DTCs, freeze frame data and misfire counts.
Turn the engine switch off and wait for at least 5 seconds.

INSPECTION PROCEDURE

HINT:

Check the "Fuel Cut Elps Time" in the Data List or the Freeze Frame Data. If the elapsed time is over 0 seconds, then the engine speed is high (engine speed at which fuel cut occurs + 500 rpm). When this has happened, there is the possibility that the valve rocker arm will become loose and a fire could start, so check that the valve rocker arm is properly attached (LandCruiser RM000002BK5053X.html).
By clearing the DTC, "Fuel Cut Elps Time" will be cleared.
If any DTCs other than misfire DTCs are output, troubleshoot those DTCs first.
Read freeze frame data using the GTS. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.
If the misfire does not recur when the vehicle is brought to the workshop, reproduce the conditions stored in the ECM as freeze frame data.
If the misfire still cannot be reproduced even though the conditions stored in the ECM as freeze frame data have been reproduced, one of the following factors is may be a cause of the problem:

There was an insufficient amount of fuel in the tank.
Improper fuel is used.
The spark plugs have been contaminated.

After finishing repairs, check the misfire counts of the cylinders (Cylinder #1 Misfire Count to Cylinder #6 Misfire Count).
Be sure to confirm that no misfiring cylinder DTCs are stored again by conducting the confirmation driving pattern after finishing repairs.
For 6 cylinders engine, the ECM intentionally does not store the specific misfiring cylinder DTCs at high engine speeds. If misfires occur only at high engine speeds, only DTC P0300 is stored.
In the event of DTC P0300 being output, perform the following operations:

Clear the DTC (LandCruiser RM000000PDK1DIX.html).
Start the engine and conduct the confirmation driving pattern.
Read the misfiring rates of each cylinder or the DTCs using the GTS.
Repair the cylinders that have a high misfiring rate or are indicated by the DTCs.
After finishing repairs, conduct the confirmation driving pattern again in order to verify that DTC P0300 is not stored.

When one of Short FT #1, Long FT #1, Short FT #2 or Long FT #2 in the freeze frame data is outside the range of +/-20%, the air fuel ratio may be Rich (-20% or less) or Lean (+20% or more).
When the Coolant Temp in the freeze frame data is below 75°C (167°F), the misfires have occurred only while the engine is being warmed up.
An extremely imbalanced drive wheel which causes body vibration may cause misfire DTCs to be stored.

1.CHECK FOR ANY OTHER DTCS OUTPUT (IN ADDITION TO MISFIRE CODES)

Connect the GTS to the DLC3.

Turn the engine switch on (IG).

Turn the GTS on.

Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

Read the DTCs.

Result
Result
Proceed to
DTC P0300, P0301, P0302, P0303, P0304, P0305 and/or P0306 are output
A
DTC P0300, P0301, P0302, P0303, P0304, P0305 and/or P0306 and other DTCs are output
B
HINT:
If any DTCs other than P0300, P0301, P0302, P0303, P0304, P0305 and/or P0306 are output, troubleshoot those DTCs first.

Result
Result	Proceed to
DTC P0300, P0301, P0302, P0303, P0304, P0305 and/or P0306 are output	A
DTC P0300, P0301, P0302, P0303, P0304, P0305 and/or P0306 and other DTCs are output	B

GO TO DTC CHART (LandCruiser RM000002ZSO015X.html)

A

2.CHECK PCV HOSE (HOSE CONNECTIONS)

Check the PCV hose connections.
OK:
PCV hose is connected correctly and is not damaged.

REPAIR OR REPLACE PCV HOSE

OK

3.READ VALUE USING GTS (MISFIRE RPM AND MISFIRE LOAD)

Connect the GTS to the DLC3.

Turn the engine switch on (IG).

Turn the GTS on.

Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Misfire RPM and Misfire Load.

Read and note the Misfire RPM and Misfire Load values.
HINT:
The Misfire RPM and Misfire Load values indicate the vehicle conditions under which the misfire occurred.

NEXT

4.READ VALUE USING GTS (CATALYST OT MF F/C)

Connect the GTS to the DLC3.

Turn the engine switch on (IG).

Turn the GTS on.

Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Catalyst OT MF F/C.

Read the value displayed on the GTS.
Result
Data List
GTS Display
Proceed to
Catalyst OT MF F/C
Avail
A
Not Avl
B

Result
Data List	GTS Display	Proceed to
Catalyst OT MF F/C	Avail	A
Not Avl	B

Go to step 6

A

5.PERFORM ACTIVE TEST USING GTS

Connect the GTS to the DLC3.

Turn the engine switch on (IG).

Turn the GTS on.

Enter the following menus: Powertrain / Engine and ECT / Active Test / Prohibit the Catalyst OT Misfire prevent F/C.

Perform the Active Test.
NOTICE:
When performing the Active Test, make sure that the vehicle is stopped and either idling or being revved at 3000 rpm or less.

NEXT

6.READ VALUE USING GTS (CYLINDER #1 (TO #6) MISFIRE COUNT)

Connect the GTS to the DLC3.

Turn the engine switch on (IG).

Turn the GTS on (Step "A").

Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Cylinder #1 (to #6) Misfire Count (Step "B").

Read each value for Cylinder #1 (to #6) Misfire Count displayed on the GTS. If no misfire counts occur in any cylinders, perform the following procedure:
1. Start the engine and let it idle.
2. Move the shift lever to D.
3. Check the Cylinder #1 (to #6) Misfire Count.
4. If misfire counts are still not displayed, perform steps ("A") and ("B").

Drive the vehicle while satisfying the Misfire RPM and Misfire Load values noted in the "Read Value Using GTS (Misfire RPM and Misfire Load)" procedure above.

Read Cylinder #1 (to #6) Misfire Count or the DTCs displayed on the GTS.

Result
Misfire Count
Proceed to
Most misfires occur in only 1 or 2 cylinders
A
3 cylinders or more have equal misfire counts
B
HINT:
1. If it is difficult to reproduce misfires for each cylinder, check the Data List item called Misfire Margin. Try to find vehicle driving conditions that lower the Misfire Margin value. Values above 30% are considered normal.
2. If the Coolant Temp value of the freeze frame data is below 75°C (167°F), the misfire may be detected only when the engine is cold.
3. If the Engine Run Time value of the freeze frame data is below 120 seconds, the misfire may be detected immediately after the engine is started.

Result
Misfire Count	Proceed to
Most misfires occur in only 1 or 2 cylinders	A
3 cylinders or more have equal misfire counts	B

Go to step 19

A

7.CHECK SPARK PLUG

Remove the ignition coil assembly and the spark plug of the misfiring cylinder.

Measure the spark plug electrode gap.
Maximum gap:
1.3 mm (0.0512 in.)

Check the electrode for carbon deposits.
Recommended Spark Plug
Manufacturer
Product
DENSO
SK16HR11
NOTICE:
If the electrode gap is larger than the maximum, replace the spark plug. Do not adjust the electrode gap.

Recommended Spark Plug
Manufacturer	Product
DENSO	SK16HR11

Reinstall the ignition coil assembly and spark plug.
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after replacing the spark plug (LandCruiser RM000004NJC03SX.html).

REPLACE SPARK PLUG (LandCruiser RM000002I2Y03MX.html)

OK

8.CHECK FOR SPARK (SPARK TEST)

Perform a spark test.
CAUTION:
During the test, disconnect all fuel injector assembly connectors.
NOTICE:
Do not crank the engine for more than 2 seconds.
1. Remove the ignition coil assembly from the cylinder head.
2. Install the spark plug to the ignition coil assembly.
3. Disconnect the 6 fuel injector assembly connectors.
4. Touch the spark plug to the cylinder head.
5. Crank the engine for less than 2 seconds and check for a spark.
  OK:
  Spark jumps across electrode gap.
6. Reconnect the 6 fuel injector assembly connectors.
7. Reinstall the ignition coil assembly.

Go to step 31

OK

9.CHECK CYLINDER COMPRESSION PRESSURE OF MISFIRING CYLINDER

Measure the cylinder compression pressure of the misfiring cylinder (LandCruiser RM0000017L801WX_01_0009.html).

CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION

OK

10.CHECK FUEL INJECTOR ASSEMBLY (POWER SOURCE)

Disconnect the fuel injector assembly connectors.

Turn the engine switch on (IG).

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
C1-1 - Body ground	Engine switch on (IG)	11 to 14 V
C2-1 - Body ground	Engine switch on (IG)	11 to 14 V
C3-1 - Body ground	Engine switch on (IG)	11 to 14 V
C4-1 - Body ground	Engine switch on (IG)	11 to 14 V
C5-1 - Body ground	Engine switch on (IG)	11 to 14 V
C6-1 - Body ground	Engine switch on (IG)	11 to 14 V

Text in Illustration
*a	Front view of wire harness connector (to Fuel Injector Assembly)

Reconnect the fuel injector assembly connectors.

CHECK FUEL INJECTOR CIRCUIT (LandCruiser RM00000330205QX.html)

OK

11.CHECK HARNESS AND CONNECTOR (FUEL INJECTOR ASSEMBLY - ECM)

Disconnect the fuel injector assembly connectors.

Disconnect the ECM connector.

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

Standard Resistance (Check for Open):

Tester Connection	Condition	Specified Condition
C1-2 - C37-6 (#10)	Always	Below 1 Ω
C2-2 - C37-1 (#20)	Always	Below 1 Ω
C3-2 - C37-7 (#30)	Always	Below 1 Ω
C4-2 - C37-2 (#40)	Always	Below 1 Ω
C5-2 - C37-8 (#50)	Always	Below 1 Ω
C6-2 - C37-3 (#60)	Always	Below 1 Ω

Standard Resistance (Check for Short):

Tester Connection	Condition	Specified Condition
C1-2 or C37-6 (#10) - Body ground	Always	10 kΩ or higher
C2-2 or C37-1 (#20) - Body ground	Always	10 kΩ or higher
C3-2 or C37-7 (#30) - Body ground	Always	10 kΩ or higher
C4-2 or C37-2 (#40) - Body ground	Always	10 kΩ or higher
C5-2 or C37-8 (#50) - Body ground	Always	10 kΩ or higher
C6-2 or C37-3 (#60) - Body ground	Always	10 kΩ or higher

Reconnect the fuel injector assembly connectors.

Reconnect the ECM connector.

REPAIR OR REPLACE HARNESS OR CONNECTOR (FUEL INJECTOR ASSEMBLY - ECM)

OK

12.INSPECT ECM TERMINAL OF MISFIRING CYLINDER (#10, #20, #30, #40, #50 AND/OR #60 VOLTAGE)

Turn the engine switch on (IG).

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

Standard Voltage:

for Automatic Transmission
Tester Connection	Switch Condition	Specified Condition
C37-6 (#10) - C37-14 (E02)	Engine switch on (IG)	11 to 14 V
C37-1 (#20) - C37-14 (E02)	Engine switch on (IG)	11 to 14 V
C37-7 (#30) - C37-14 (E02)	Engine switch on (IG)	11 to 14 V
C37-2 (#40) - C37-14 (E02)	Engine switch on (IG)	11 to 14 V
C37-8 (#50) - C37-14 (E02)	Engine switch on (IG)	11 to 14 V
C37-3 (#60) - C37-14 (E02)	Engine switch on (IG)	11 to 14 V

for Manual Transmission
Tester Connection	Switch Condition	Specified Condition
C37-6 (#10) - C37-14 (E01)	Engine switch on (IG)	11 to 14 V
C37-1 (#20) - C37-14 (E01)	Engine switch on (IG)	11 to 14 V
C37-7 (#30) - C37-14 (E01)	Engine switch on (IG)	11 to 14 V
C37-2 (#40) - C37-14 (E01)	Engine switch on (IG)	11 to 14 V
C37-8 (#50) - C37-14 (E01)	Engine switch on (IG)	11 to 14 V
C37-3 (#60) - C37-14 (E01)	Engine switch on (IG)	11 to 14 V

Text in Illustration
*A	for Manual Transmission
*B	for Automatic Transmission
*a	Component with harness connected (ECM)

Reconnect the ECM connector.

REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - BODY GROUND)

OK

13.CHECK FUEL INJECTOR ASSEMBLY OF MISFIRING CYLINDER

Check the fuel injector assembly injection (whether fuel volume is high or low, and whether injection pattern is poor) (LandCruiser RM000000WQQ0BHX.html).
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after replacing the fuel injector assembly (LandCruiser RM000004NJC03SX.html).

REPLACE FUEL INJECTOR ASSEMBLY (LandCruiser RM000000Q480CHX.html)

OK

14.INSPECT INTAKE SYSTEM

Check the intake system for vacuum leaks (LandCruiser RM0000046C000QX_01_0001.html).
OK:
No leaks in intake system.
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after repairing or replacing the intake system (LandCruiser RM000004NJC03SX.html).

REPAIR OR REPLACE INTAKE SYSTEM

OK

15.CHECK FUEL PRESSURE

Check the fuel pressure (LandCruiser RM000000YL706HX_01_0002.html).

Go to step 33

OK

16.READ VALUE USING GTS (COOLANT TEMP)

Connect the GTS to the DLC3.

Turn the engine switch on (IG).

Turn the GTS on.

Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.

Read the Coolant Temp twice when the engine is both cold and warmed up.
Standard:
With cold engine:
Same as ambient temperature.
With warm engine:
Between 75°C and 95°C (167°F and 203°F).
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after replacing the engine coolant temperature sensor (LandCruiser RM000004NJC03SX.html).

REPLACE ENGINE COOLANT TEMPERATURE SENSOR (LandCruiser RM000000PWT056X.html)

OK

17.INSPECT MASS AIR FLOW METER

Inspect the mass air flow meter (LandCruiser RM000002PPR02RX.html).
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after replacing the mass air flow meter sub-assembly (LandCruiser RM000004NJC03SX.html).

REPLACE MASS AIR FLOW METER (LandCruiser RM000000VW603AX.html)

OK

18.CHECK VALVE TIMING

Check the valve timing (LandCruiser RM000000PDU0YWX_09_0005.html).

CHECK ENGINE MECHANICAL SYSTEM (LandCruiser RM000002BK3041X.html)

REPLACE ECM (LandCruiser RM00000329203TX.html)

19.CHECK INTAKE SYSTEM

Check the intake system for vacuum leaks (LandCruiser RM0000046C000QX_01_0001.html).
OK:
No leaks in intake system.
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after repairing or replacing the intake system (LandCruiser RM000004NJC03SX.html).

REPAIR OR REPLACE INTAKE SYSTEM

OK

20.CHECK FUEL PRESSURE

Check the fuel pressure (LandCruiser RM000000YL706HX_01_0002.html).

Go to step 33

OK

21.READ VALUE USING GTS (COOLANT TEMP)

Connect the GTS to the DLC3.

Turn the engine switch on (IG).

Turn the GTS on.

Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.

Read the Coolant Temp twice when the engine is both cold and warmed up.
Standard:
With cold engine:
Same as ambient air temperature.
With warm engine:
Between 75°C and 95°C (167°F and 203°F).
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after replacing the engine coolant temperature sensor (LandCruiser RM000004NJC03SX.html).

REPLACE ENGINE COOLANT TEMPERATURE SENSOR (LandCruiser RM000000PWT056X.html)

OK

22.INSPECT MASS AIR FLOW METER

Inspect the mass air flow meter (LandCruiser RM000002PPR02RX.html).
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after replacing the mass air flow meter sub-assembly (LandCruiser RM000004NJC03SX.html).

REPLACE MASS AIR FLOW METER (LandCruiser RM000000VW603AX.html)

OK

23.CHECK VALVE TIMING

Check the valve timing (LandCruiser RM000000PDU0YWX_09_0005.html).

CHECK ENGINE MECHANICAL SYSTEM (LandCruiser RM000002BK3041X.html)

OK

24.CHECK SPARK PLUG

Remove the ignition coil assembly and the spark plug of the misfiring cylinder.

Measure the spark plug electrode gap.
Maximum gap:
1.3 mm (0.0512 in.)

Check the electrode for carbon deposits.
Recommended Spark Plug
Manufacturer
Product
DENSO
SK16HR11
NOTICE:
If the electrode gap is larger than the maximum, replace the spark plug. Do not adjust the electrode gap.

Reinstall the ignition coil assembly and spark plug.
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after replacing the spark plug (LandCruiser RM000004NJC03SX.html).

REPLACE SPARK PLUG (LandCruiser RM000002I2Y03MX.html)

OK

25.CHECK FOR SPARK (SPARK TEST)

Perform a spark test.
CAUTION:
During the test, disconnect all fuel injector assembly connectors.
NOTICE:
Do not crank the engine for more than 2 seconds.
1. Remove the ignition coil assembly from the cylinder head.
2. Install the spark plug to the ignition coil assembly.
3. Disconnect the 6 fuel injector assembly connectors.
4. Touch the spark plug to the cylinder head.
5. Crank the engine for less than 2 seconds and check for a spark.
  OK:
  Spark jumps across electrode gap.
6. Reconnect the 6 fuel injector assembly connectors.
7. Reinstall the ignition coil assembly.

Go to step 31

OK

26.CHECK CYLINDER COMPRESSION PRESSURE OF MISFIRING CYLINDER

Measure the cylinder compression pressure of the misfiring cylinder (LandCruiser RM0000017L801WX_01_0009.html).

CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION

OK

27.CHECK FUEL INJECTOR ASSEMBLY (POWER SOURCE)

Disconnect the fuel injector assembly connectors.

Turn the engine switch on (IG).

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
C1-1 - Body ground	Engine switch on (IG)	11 to 14 V
C2-1 - Body ground	Engine switch on (IG)	11 to 14 V
C3-1 - Body ground	Engine switch on (IG)	11 to 14 V
C4-1 - Body ground	Engine switch on (IG)	11 to 14 V
C5-1 - Body ground	Engine switch on (IG)	11 to 14 V
C6-1 - Body ground	Engine switch on (IG)	11 to 14 V

Text in Illustration
*a	Front view of wire harness connector (to Fuel Injector Assembly)

Reconnect the fuel injector assembly connectors.

CHECK FUEL INJECTOR CIRCUIT (LandCruiser RM00000330205QX.html)

OK

28.CHECK HARNESS AND CONNECTOR (FUEL INJECTOR ASSEMBLY - ECM)

Disconnect the fuel injector assembly connectors.

Disconnect the ECM connector.

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

Standard Resistance (Check for Open):

Tester Connection	Condition	Specified Condition
C1-2 - C37-6 (#10)	Always	Below 1 Ω
C2-2 - C37-1 (#20)	Always	Below 1 Ω
C3-2 - C37-7 (#30)	Always	Below 1 Ω
C4-2 - C37-2 (#40)	Always	Below 1 Ω
C5-2 - C37-8 (#50)	Always	Below 1 Ω
C6-2 - C37-3 (#60)	Always	Below 1 Ω

Standard Resistance (Check for Short):

Tester Connection	Condition	Specified Condition
C1-2 or C37-6 (#10) - Body ground	Always	10 kΩ or higher
C2-2 or C37-1 (#20) - Body ground	Always	10 kΩ or higher
C3-2 or C37-7 (#30) - Body ground	Always	10 kΩ or higher
C4-2 or C37-2 (#40) - Body ground	Always	10 kΩ or higher
C5-2 or C37-8 (#50) - Body ground	Always	10 kΩ or higher
C6-2 or C37-3 (#60) - Body ground	Always	10 kΩ or higher

Reconnect the fuel injector assembly connectors.

Reconnect the ECM connector.

REPAIR OR REPLACE HARNESS OR CONNECTOR (FUEL INJECTOR ASSEMBLY - ECM)

OK

29.INSPECT ECM TERMINAL OF MISFIRING CYLINDER (#10, #20, #30, #40, #50 AND/OR #60 VOLTAGE)

Turn the engine switch on (IG).

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

Standard Voltage:

for Automatic Transmission
Tester Connection	Switch Condition	Specified Condition
C37-6 (#10) - C37-14 (E02)	Engine switch on (IG)	11 to 14 V
C37-1 (#20) - C37-14 (E02)	Engine switch on (IG)	11 to 14 V
C37-7 (#30) - C37-14 (E02)	Engine switch on (IG)	11 to 14 V
C37-2 (#40) - C37-14 (E02)	Engine switch on (IG)	11 to 14 V
C37-8 (#50) - C37-14 (E02)	Engine switch on (IG)	11 to 14 V
C37-3 (#60) - C37-14 (E02)	Engine switch on (IG)	11 to 14 V

for Manual Transmission
Tester Connection	Switch Condition	Specified Condition
C37-6 (#10) - C37-14 (E01)	Engine switch on (IG)	11 to 14 V
C37-1 (#20) - C37-14 (E01)	Engine switch on (IG)	11 to 14 V
C37-7 (#30) - C37-14 (E01)	Engine switch on (IG)	11 to 14 V
C37-2 (#40) - C37-14 (E01)	Engine switch on (IG)	11 to 14 V
C37-8 (#50) - C37-14 (E01)	Engine switch on (IG)	11 to 14 V
C37-3 (#60) - C37-14 (E01)	Engine switch on (IG)	11 to 14 V

Text in Illustration
*A	for Manual Transmission
*B	for Automatic Transmission
*a	Component with harness connected (ECM)

Reconnect the ECM connector.

REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - BODY GROUND)

OK

30.CHECK FUEL INJECTOR ASSEMBLY OF MISFIRING CYLINDER

Check the fuel injector assembly injection (whether fuel volume is high or low, and whether injection pattern is poor) (LandCruiser RM000000WQQ0BHX.html).
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after replacing the fuel injector assembly (LandCruiser RM000004NJC03SX.html).

REPLACE FUEL INJECTOR ASSEMBLY (LandCruiser RM000000Q480CHX.html)

REPLACE ECM (LandCruiser RM00000329203TX.html)

31.CHANGE TO KNOWN GOOD SPARK PLUG AND CHECK SPARK OF MISFIRING CYLINDER

Change the installed spark plug to a known good spark plug.

Perform a spark test.
CAUTION:
During the test, disconnect all fuel injector assembly connectors.
NOTICE:
Do not crank the engine for more than 2 seconds.
1. Remove the ignition coil assembly from the cylinder head.
2. Install the spark plug to the ignition coil assembly.
3. Disconnect the 6 fuel injector assembly connectors.
4. Touch the spark plug to the cylinder head.
5. Crank the engine for less than 2 seconds and check for a spark.
  OK:
  Spark jumps across electrode gap.
6. Reconnect the 6 fuel injector assembly connectors.
7. Reinstall the ignition coil assembly.

HINT:
for Automatic Transmission

Perform "Inspection After Repair" after replacing the spark plug (LandCruiser RM000004NJC03SX.html).

Go to step 32

REPLACE SPARK PLUG (LandCruiser RM000002I2Y03MX.html)

32.CHANGE TO KNOWN GOOD IGNITION COIL ASSEMBLY AND CHECK SPARK OF MISFIRING CYLINDER

Change the installed ignition coil assembly to a known good ignition coil assembly.

Perform a spark test.
CAUTION:
During the test, disconnect all fuel injector assembly connectors.
NOTICE:
Do not crank the engine for more than 2 seconds.
1. Remove the ignition coil assembly from the cylinder head.
2. Install the spark plug onto the ignition coil assembly.
3. Disconnect the 6 fuel injector assembly connectors.
4. Touch the spark plug to the cylinder head.
5. Crank the engine for less than 2 seconds and check for spark.
  OK:
  Spark jumps across electrode gap.
6. Reconnect the 6 fuel injector assembly connectors.
7. Reinstall the ignition coil assembly.

HINT:
for Automatic Transmission

Perform "Inspection After Repair" after replacing the ignition coil assembly (LandCruiser RM000004NJC03SX.html).

REPLACE ECM (LandCruiser RM00000329203TX.html)

REPLACE IGNITION COIL ASSEMBLY (LandCruiser RM000002I2Y03MX.html)

33.CHECK FUEL LINE

Check the fuel lines for leaks or blockage.
Result
Result
Proceed to
NG
A
OK (for Single Tank Type)
B
OK (for Double Tank Type)
C
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after replacing the fuel pump (LandCruiser RM000004NJC03SX.html).

REPLACE FUEL PUMP (LandCruiser RM0000045QT00YX.html)

REPLACE FUEL PUMP (LandCruiser RM0000045QX00BX.html)

REPAIR OR REPLACE FUEL LINE

Engine Speed	Duration
Idling	8 minutes or more
1000	4.5 minutes or more
2000	2.5 minutes or more
3000	1.5 minutes or more

Result	Proceed to
NG	A
OK (for Single Tank Type)	B
OK (for Double Tank Type)	C