DTC P0168
Precautions: General safety (00)
DTC Detecting Condition and Trouble Area
| DTC detection condition | Trouble area |
|---|---|
|
P0168: Fuel Temperature Too High Limited value of fuel quantity is higher than specified value which varies depending on fuel temperature and engine speed. (1 D/C detection logic but MIL does not light up) |
•Fuel temperature sensor and/or its circuit
•Fuel heater and/or its circuit •Engine cooling system •Engine oil insufficient •ECM |
Circuit Diagram
| [A]: | ECM connector (View: [a]) | B3: | Fuel heater relay drive circuit | 3. | Fuel heater |
| A1: | Fuel temperature sensor signal circuit | C1: | Fuel heater power supply circuit | 4. | Fuel heater relay |
| A2: | Fuel temperature sensor ground circuit | C2: | Fuel heater ground circuit | 5. | “FUEL HTR” fuse |
| B1: | Fuel heater relay power supply circuit (coil side) | 1. | ECM | ||
| B2: | Fuel heater relay power supply circuit (switch side) | 2. | Fuel temperature sensor |
DTC Troubleshooting
| Step | Action | Yes | No |
|---|---|---|---|
| 1 |
Was “Engine and Emission Control System Check” performed?
|
Go to Step 2.
|
|
| 2 |
Fuel temperature sensor signal circuit and ground circuit check
1)Check “A1” and “A2” circuits according to Step 2 of Fuel Temperature Sensor Check:D16AA.
Is check result OK?
|
Go to Step 3.
|
Repair or replace defective wire harness.
|
| 3 |
Fuel temperature sensor check
1)Check fuel temperature sensor.
Is check result OK?
|
Go to Step 4.
|
Replace fuel filter assembly.
|
| 4 |
Fuel heater operation check
1)Check fuel heater operation.
Is check result OK?
|
Go to Step 5.
|
Repair or replace defective part(s).
|
| 5 |
Cooling system check
1)Check cooling system.
•Coolant level:
•Engine cooling system: Is check result OK?
|
Go to Step 6.
|
Repair or replace defective part(s).
|
| 6 |
Engine lubrication system check
1)Check that there is no engine oil leakage and engine oil level is correct.
Is check result OK?
|
Go to Step 7.
|
Repair or replace defective part(s).
|
| 7 |
Engine speed check
1)Check that engine speed is correct.
Is check result OK?
|
Replace ECM and recheck DTC.
|
End.
|