P0183
Fuel Temperature Sensor Circuit:
Connectors:
CIRCUIT OPERATION
- 5-volt voltage is applied to the fuel temperature sensor output terminal (terminal 3) from the ECM (terminal 77)
- The fuel temperature sensor output voltage increases when the resistance increases and decreases when the resistance decreases. The ground terminal (terminal 2) is grounded to the vehicle body.
TECHNICAL DESCRIPTION
- The fuel temperature sensor converts the fuel temperature to a voltage.
- The ECM
DTC SET CONDITIONS
Check Conditions
- 2 seconds or more have passed since the starting sequence was completed.
Judgement Criteria
- Fuel temperature sensor output voltage has continued to be 4.6 volts or higher for 2 seconds.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Fuel temperature sensor failed.
- Open or shorted fuel temperature sensor circuit, or loose connector.
- ECM failed.
- PCM failed.
DIAGNOSIS
Required Special Tools
- MB991502: Scan Tool (MUT-II)
STEP 1. Using scan tool MB991502, check data list item 4A: Fuel Temperature Sensor.
CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
1. Connect scan tool MB991502 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991502 to the data reading mode for item 4A, Fuel Temperature Sensor.
- Approximately the same as the outside temperature when the engine is cooled.
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. Refer to How to Use Troubleshooting/Inspection Service Points.
NO: Go to Step 2.
STEP 2. Check connector D-10 at the fuel temperature sensor for damage.
Q: Is the connector in good condition?
YES: Go to Step 3.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 11.
STEP 3. Check the fuel temperature sensor.
1. Disconnect the fuel temperature sensor connector D-10
2. Measure the resistance between terminal 2 and 3 of the fuel temperature sensor
Standard value: 0.5 - 12.0 kohm
Q: Is the resistance at the standard value?
YES:Go to Step 4.
NO: Replace the fuel temperature sensor. Then go to Step 11.
STEP 4. Check the sensor supply voltage at fuel 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 3 and ground.
- Voltage should be between 4.5 and 4.9 volts
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the voltage normal?
YES: Go to Step 8.
NO: Go to Step 5.
STEP 5. Check the sensor supply voltage at ECM connector C-115
1. Do not disconnect the ECM connector C-115
2. Disconnect the fuel temperature sensor connector D-10.
3. Turn the ignition switch to the "ON" position.
4. Measure the voltage between terminal 77
- Voltage should be between 4.5 and 4.9 volts.
5. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the voltage normal?
YES: Go to Step 6.
NO: Go to Step 7.
STEP 6. Check connector C-115 at ECM
Q: Is the connector in good condition?
YES: Check connector C-122, C-127 and D-14 at intermediate connector for damage, and repair or replace as required. Refer to Harness Connector Inspection. If intermediate connector are in good condition, repair harness wire between fuel temperature sensor connector D-10 terminal 3 and ECM connector C-115 terminal 77
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 11.
STEP 7. Check connector C-115 at ECM
Q: Is the connector in good condition?
YES: Replace the ECM or PCM. Then go to Step 11.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 11.
STEP 8. Check the continuity at fuel 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 2 and ground.
- Should be less than 2 ohm.
Q: Is the continuity normal?
YES: Go to Step 9.
NO: Check connector D-14 at intermediate connector for damage, and repair or replace as required. Refer to Harness Connector Inspection. If intermediate connector is in good condition, repair harness wire between fuel temperature sensor connector D-10 terminal 2 and ground because of open circuit or harness damage. Then go to Step 11.
STEP 9. Check connector C-115 at ECM
Q: Is the connector in good condition?
YES: Go to Step 10.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 11.
STEP 10. Check for open circuit and harness damage between fuel temperature sensor connector D-10 and ECM connector C-115
NOTE: Check harness after checking intermediate connector C-122, C-127 and D-14. If intermediate connector are damaged, repair or replace it. Refer to Harness Connector Inspection. Then go to Step 11.
Q: Is the harness wire in good condition?
YES: Replace the ECM or PCM. Then go to Step 11.
NO: Repair it. Then go to Step 11.
STEP 11. Test the OBD-II drive cycle.
1. Carry out a test drive with the drive cycle pattern. Refer to, Procedure 6 - Other Monitor.
2. Check the diagnostic trouble code (DTC)
Q: Is the DTC P0183 output?
YES: Retry the troubleshooting.
NO: The inspection is complete.