P0181
DTC P0181 FTT SENSORComponent Description
The fuel tank temperature (FTT) sensor is used to detect the fuel temperature inside the fuel tank. The sensor modifies a voltage signal from the ECM. The modified signal returns to the ECM as the fuel temperature input. The sensor uses a thermistor which is sensitive to the change in temperature. The electrical resistance of the thermistor decreases as temperature increases.
CAUTION: Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis Logic
DTC Confirmation Procedure
NOTE: If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.
WITH CONSULT-III
1. Turn ignition switch ON and wait at least 10 seconds.
2. Wait at least 10 seconds.
If 1st trip DTC is detected, go to "Diagnosis Procedure".
If 1st trip DTC is not detected, go to following step.
3. Select "DATA MONITOR" mode with CONSULT-III.
4. Check "COOLAN TEMP/S" value.
If "COOLAN TEMP/S" is less than 60 °C (140 °F), the result will be OK.
If "COOLAN TEMP/S" is above 60 °C (140 °F), go to the following step.
5. Cool engine down until "COOLAN TEMP/S" is less than 60 °C (140 °F).
6. Wait at least 10 seconds.
7. Check 1st trip DTC.
8. If 1st trip DTC is detected, go to "Diagnosis Procedure".
WITH GST
Follow the procedure "WITH CONSULT-III" above.
Wiring Diagram
EC-FTTS-01:
Diagnosis Procedure
Step 1-4:
Step 5-8:
Component Inspection
FUEL TANK TEMPERATURE SENSOR
1. Remove fuel level sensor unit.
2. Check resistance between "fuel level sensor unit and fuel pump" terminals 4 and 5 by heating with hot water as shown in the figure.
If NG, replace fuel level sensor unit.