P0181

DTC P0181 FUEL TEMP SENSOR A CIRCUIT RANGE/PERFORMANCE

Component Location:

COMPONENT LOCATION

GENERAL DESCRIPTION
The fuel temperature sensor is located in the fuel tank for detecting the fuel tank temperature.

The fuel temperature sensor uses a thermistor whose resistance changes with the temperature.

The electrical resistance of the fuel temperature sensor decreases as the temperature increases, and increases as the temperature decreases.

The reference 5 V in the PCM is supplied to the fuel temperature sensor via a resistor in the PCM. The resistor in the PCM and the thermistor in the fuel temperature sensor are connected in series. When the resistance value of the thermistor in fuel temperature sensor changes with variations in fuel tank temperature, the output voltage also changes.

DTC DESCRIPTION
If the voltage difference between fuel tank temperature and engine coolant temperature is higher than threshold value at starting, the PCM determines that a fault exists and a DTC is stored.

DTC Detecting Condition:

DTC DETECTING CONDITION

Specification:

SPECIFICATION

Schematic Diagram:

SCHEMATIC DIAGRAM

COMPONENT INSPECTION
1. Ignition "OFF"
2. Disconnect Fuel Tank Unit connector.




3. Measure resistance between terminal 1 and 4 of the Fuel Temperature Sensor connector (To Component Side).

Specification :
At 0 °C (32 °F), Resistance 4 - 7 k Ohm
At 20 °C(68 °F), Resistance 2 - 3 kOhm
At 40 °C(104 °F), Resistance 0.9 - 1.3 kOhm
At 80 °C(176 °F), Resistance 0.2 - 0.4 kOhm

4. Is the measured resistance of FTS within specifications ?

YES: Substitute with a known - good PCM and check for proper operation.

If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.

NO: Substitute with a known - good FTS and check for proper operation.

If the problem is corrected, replace FTS and go to "Verification of Vehicle Repair" procedure.

VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code(DTC) which has been diagnosed.
2. Using a Scantool, Clear the DTCs.
3. Operate the vehicle within conditions noted in the freeze frame data or enable conditions.
4. Monitor that all readiness test have been verified as "Complete"
5. Are any DTCs present ?

YES: Go to the applicable troubleshooting procedure.

NO: System is performing to specification at this time.