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P0183

DTC P0183: Fuel Tank Temperature Sensor Circuit High Input

Fuel Tank Temperature Sensor Circuit Part 1:




Fuel Tank Temperature Sensor Circuit Part 2:






CIRCUIT OPERATION
- 5-volt voltage is applied to the fuel tank temperature sensor output terminal (terminal No. 3) from the ECM or the PCM (terminal No. 81) via the resistor in the ECM or the PCM .
- The fuel tank temperature sensor output voltage increases when the resistance increases and decreases when the resistance decreases. The ground terminal (terminal No. 2) is grounded to the vehicle body.

TECHNICAL DESCRIPTION
- The fuel tank temperature sensor converts the fuel tank temperature to a voltage.
- The ECM or the PCM
detects the fuel tank temperature with this output voltage.

DESCRIPTIONS OF MONITOR METHODS
Fuel tank temperature sensor output voltage is out of specified range.

MONITOR EXECUTION
Continuous

MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)

Other Monitor (There is no temporary DTC stored in memory for the item monitored below)
- Not applicable

Sensor (The sensor below is determined to be normal)
- Engine coolant temperature sensor
- Intake air temperature sensor

DTC SET CONDITIONS

Logic Flow Chart:




Logic Flow Chart

Check Condition
- 2 seconds or more have passed since the engine starting sequence was completed.

Judgement Criterion
- Sensor output voltage has continued to be 4.6 volts or higher for 2 seconds.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 22
OBD-II Drive Cycle Pattern Lists.

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Fuel tank temperature sensor failed.
- Open fuel tank temperature sensor circuit or connector damage.
- ECM failed.
- PCM failed.

DIAGNOSIS

Required Special Tools:
- MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991911: Main Harness B

STEP 1. Using scan tool MB991958, check data list item 4A: Fuel Tank Temperature Sensor.

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.




1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to the data reading mode for item 4A, Fuel Tank Temperature Sensor.
- With the engine cool, the fuel tank temperature should be approximately the same as ambient air temperature.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the sensor operating properly?

YES: It can be assumed that this malfunction is intermittent.

NO: Go to Step 2.




STEP 2. Check harness connector D-10 at the fuel tank temperature sensor for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 3.

NO: Repair or replace it. Then go to Step 10.

STEP 3. Check the fuel tank temperature sensor.




1. Disconnect the fuel tank temperature sensor connector D-10.




2. Measure the resistance between terminal No. 2 and No. 3 of the fuel tank temperature sensor.
Standard value: 0.5 - 12.0 kohm

Q: Is the measured resistance between 0.5 and 12.0 kOhms?

YES: Go to Step 4.

NO: Replace the fuel tank temperature sensor. Then go to Step 10.

STEP 4. Check the sensor supply voltage at fuel tank temperature sensor harness side connector D-10.




1. Disconnect the connector D-10 and measure at the harness side.
2. Turn the ignition switch to the "ON" position.




3. Measure the voltage between terminal No. 3 and ground.
- Voltage should measure between 4.5 and 4.9 volts

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage between 4.5 and 4.9 volts?

YES: Go to Step 8.

NO: Go to Step 5.

STEP 5. Measure the sensor supply voltage at ECM connector C-137 or PCM connector C-138
by backprobing.




1. Do not disconnect the ECM connector C-137 or PCM connector C-138
.
2. Disconnect the fuel tank temperature sensor connector D- 10.
3. Turn the ignition switch to the "ON" position.




4. Measure the voltage between terminal No. 81 and ground by backprobing.
- Voltage should be between 4.5 and 4.9 volts.

5. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage between 4.5 and 4.9 volts?

YES: Go to Step 6.

NO: Go to Step 7.




STEP 6. Check harness connector C-137 at ECM or C-138 at PCM
for damage.

Q: Is the harness connector in good condition?

YES: Check harness connector C-122, C-127 and D-14 at intermediate connector for damage, and repair or replace as required. If intermediate connectors are in good condition, repair harness wire between fuel tank temperature sensor connector D-10 (terminal No. 3) and ECM connector C-137 or PCM connector C-138
(terminal No. 81) because of open circuit. Then go to Step 10.

NO: Repair or replace it. +Then go to Step 10.




STEP 7. Check harness connector C-137 at ECM or C-138 at PCM
for damage.

Q: Is the harness connector in good condition?

YES: Replace the ECM or the PCM. Then go to Step 10.

NO: Repair or replace it. Then go to Step 10.

STEP 8. Check the continuity at fuel tank temperature sensor harness side connector D-10.




1. Disconnect the connector D-10 and measure at the harness side.




2. Check for the continuity between terminal No. 2 and ground.
- Should be less than 2 Ohms.

Q: Does continuity exist?

YES: Go to Step 9.

NO: Check harness connector D-14 at intermediate connector for damage, and repair or replace as required. If intermediate connector is in good condition, repair harness wire between fuel tank temperature sensor connector D-10 (terminal No. 2) and ground because of harness damage. Then go to Step 10.




STEP 9. Check harness connector C-137 at ECM or C-138 at PCM
for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 10.

NO: Repair or replace it. Then go to Step 10.

STEP 10. Test the OBD-II drive cycle.

1. Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 22
OBD-II Drive Cycle Pattern Lists.
2. Check the diagnostic trouble code (DTC).

Q: Is DTC P0183 set?

YES: Retry the troubleshooting.

NO: The inspection is complete.