B1201
DTC B1201: Defective fuel gaugeFuel Gauge Circuit:
CAUTION:
- If DTC B1201 is set in the combination meter, always diagnose the CAN bus lines.
- Whenever the ECU is replaced, ensure that the communication circuit is normal.
CIRCUIT OPERATION
The fuel gauge displays the amount of the remaining fuel on the combination meter.
DTC SET CONDITION
DTC B1201 is set if an open circuit and short to ground in the fuel sender circuit are detected for 64 seconds or more when the ignition switch is ON.
TECHNICAL DESCRIPTION (COMMENT)
The wiring harness or connectors may have loose, corroded, or damage terminals, or terminals pushed back in the connector, or the combination meter may be defective.
TROUBLESHOOTING HINTS
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
- Malfunction of powertrain control module
- Malfunction of fuel level sensor (sub)
- Malfunction of fuel pump module
- Malfunction of combination meter
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicles Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)
- MB991223: Harness Set
- MB992006: Extra Fine Probe
STEP 1. Using scan tool MB991958, read the MFI system diagnostic trouble code.
Check if an MFI system DTC is set.
Q: Is the DTC set?
YES : Diagnose the MFI system by referring to MFI Diagnosis - Diagnostic Trouble Code Chart [2.4L ENGINE] Diagnostic Trouble Code Descriptions or MFI Diagnosis - Diagnostic Trouble Code Chart [3.8L ENGINE]. Diagnostic Trouble Code Descriptions
NO : Go to Step 2.
STEP 2. Using scan tool MB991958, check data list.
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 actuator test mode.
- Item 89: Fuel gauge.
- Fuel gauge unit resistance value and scan tool displayed value agree with each other.
- Item 8A: Fuel gauge (Target).
- Fuel gauge and scan tool displayed values agree with each other.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the solenoid valve operating properly?
YES : Go to Step 18.
NO : Go to Step 3.
STEP 3. Check fuel level sensor (sub) connector D-17 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is fuel level sensor (sub) connector D-17 in good condition?
YES : Go to Step 4.
NO : Repair or replace the damaged component(s). The combination meter work normally.
STEP 4. Check the fuel level sensor (sub).
Check to see if the fuel level sensor (sub) is normal. Fuel Level Sensor Check
Q: Is the fuel level sensor (sub) normal?
YES : Go to Step 5.
NO : Replace the fuel level sensor.
STEP 5. Check fuel pump module connector D-18 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is fuel pump module connector D-18 in good condition?
YES : Go to Step 6.
NO : Repair or replace the damaged component(s). Verify that the combination meter work normally.
STEP 6. Check the fuel pump module.
Check to see if the fuel pump module is normal. Fuel Level Sensor Check
Q: Is the fuel pump module normal?
YES : Go to Step 7.
NO : Replace the fuel pump module. The fuel gauge should now operate normally.
STEP 7. Check the ground circuit to the fuel pump module. Measure the resistance at fuel pump module connector D-18.
1. Disconnect fuel pump module connector D-18 and measure the resistance available at the harness side of the connector.
2. Measure the resistance value between terminal 1 and ground.
- The resistance should be 2 ohms or less.
Q: Is the measured resistance 2 ohms or less?
YES : Go to Step 8.
NO : Go to Step 9.
STEP 8. Check the wiring harness between fuel pump module connector D-18 (terminal 1) and ground.
- Check the ground wire for open circuit.
Q: Is the wiring harness between fuel pump module connector D-18 (terminal 1) and ground in good condition?
YES : An intermittent malfunction is suspected.
NO : The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the combination meter work normally.
STEP 9. Check the wiring harness between fuel level sensor (sub) connector D-17 (terminal 1) and fuel pump module connector D-18 (terminal 2)
- Check the communication lines for open circuit and short circuit.
1. Disconnect fuel level sensor (sub) connector D-17 and fuel pump module connector D-18, and measure the resistance at the wiring harness side.
2. Measure the resistance between fuel level sensor (sub) connector D-17 terminal 1 and fuel pump module connector D-18 terminal 2.
- The resistance should be 2 ohms or less.
Q: Is the measured resistance 2 ohms or less?
YES : Go to Step 10.
NO : Repair the wiring harness.
STEP 10. Check combination meter connector C-101 and powertrain control module connector B-20 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are combination meter connector C-101 and powertrain control module connector B-20 in good condition?
YES : Go to Step 11.
NO : Repair or replace the damaged component(s). Verify that the combination meter work normally.
STEP 11. Check the wiring harness between combination meter connector C-101 (terminal 13) and fuel level sensor (sub) connector D-17 (terminal 2).
- Check the communication lines for open circuit and short circuit.
NOTE: Also check intermediate connector C-28 for loose, corroded, or damaged terminals, or terminals pushed back in the connector.
1. Disconnect combination meter connector C-101 and fuel level sensor (sub) connector D-17, and measure the resistance at the wiring harness side.
2. Measure the resistance between combination meter connector C-101 terminal 13 and fuel level sensor (sub) connector D-17 terminal 2.
- The resistance should be 2 ohms or less.
Q: Is the measured resistance 2 ohms or less?
YES : Go to Step 12.
NO : Repair the wiring harness.
STEP 12. Check the wiring harness between combination meter and the fuel level sensor (sub) for short to ground. Measure the resistance at combination meter connector C-101.
1. Disconnect combination meter connector C-101 and fuel level sensor (sub) connector D-17, and measure the resistance available at the harness side of the combination meter connector C-101.
2. Measure the resistance value between terminal 13 and ground.
- The resistance should be 1 kohm or more.
Q: Is the measured resistance 1 k ohm or more?
YES : Go to Step 14.
NO : Go to Step 13.
STEP 13. Check the wiring harness between combination meter connector C-101 (terminal 13) and fuel level sensor (sub) connector D-17 (terminal 2).
- Check the communication lines for open circuit and short circuit.
NOTE: Also check intermediate connector C-28 for loose, corroded, or damaged terminals, or terminals pushed back in the connector.
Q: Is the wiring harness between combination meter connector C-101 (terminal 13) and fuel level sensor (sub) connector D-17 (terminal 2) in good condition?
YES : An intermittent malfunction is suspected.
NO : The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the combination meter work normally.
STEP 14. Check the wiring harness between fuel level sensor (sub), the fuel pump module and the powertrain control module for short to ground. Measure the resistance at fuel level sensor (sub) connector D-17.
1. Disconnect fuel level sensor (sub) connector D-17, fuel pump module connector D-18 and powertrain control module connector B-20, and measure the resistance available at the harness side of the fuel level sensor (sub) connector D-17.
2. Measure the resistance value between terminal 1 and ground.
- The resistance should be 1 kohms or more.
Q: Is the measured resistance 1 kohms or more?
YES : Go to Step 17.
NO : Go to Step 15.
STEP 15. Check the wiring harness between fuel level sensor (sub) connector D-17 (terminal 1) and fuel pump module connector D-18 (terminal 2).
- Check the communication lines for open circuit and short circuit.
Q: Is the wiring harness between fuel level sensor connector D-17 (terminal 1) and fuel pump module connector D-18 (terminal 2) in good condition?
YES : Go to Step 16.
NO : The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the combination meter work normally.
STEP 16. Check the wiring harness between fuel level sensor (sub) connector D-17 (terminal 1) and powertrain control module connector B-20 (terminal 24).
- Check the communication lines for open circuit and short circuit.
NOTE: Also check intermediate connector C-25 for loose, corroded, or damaged terminals, or terminals pushed back in the connector.
Q: Is the wiring harness between fuel level sensor connector D-17 (terminal 1) and powertrain control module connector B-20 (terminal 24) in good condition?
YES : Go to Step 17.
NO : The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the combination meter work normally.
STEP 17. Replace the combination meter, and then recheck the DTC.
Replace the combination meter, and then check that the DTC is not reset.
Q: Is the check result normally?
YES : The procedure is complete.
NO : Replace powertrain control module. When the powertrain control module is replaced, register the encrypted code.
STEP 18. Recheck for diagnostic trouble code.
Recheck if the DTC is set.
1. Erase the DTC.
2. Turn the ignition switch to "OFF" position.
3. Turn the ignition switch to "ON" position.
4. Drive the vehicle and check that the diagnostic trouble code is not set.
Q: Is the check result satisfactory?
YES : The procedure is complete.
NO : Replace combination meter.