Part 2 of 2
STEP 12. Check the signal voltage at fuel tank differential pressure sensor connector D-09.1. Remove the fuel tank. (Refer to Fuel Tank.)
2. Plug the filler hose, fuel pump feed nipple, hose H, hose L and hose Q connected to the fuel tank.
NOTE: If these items are not securely plugged here, the fuel could leak in the next step.
3. Lift the fuel tank.
4. Connect special tool MB991658 to both halves of connector D-09.
5. Turn the ignition switch to the "ON" position.
6. Measure the voltage between connector D-09 terminal 2 and ground.
- The measured voltage should be 0.5 volt or less.
7. Connect an evaporative emission system pressure pump (Miller number 6872A) to the fuel filler neck and pressurize the fuel tank.
- The fuel tank pressure reading should increase.
8. Turn the ignition switch to the "LOCK" (OFF) position.
9. Disconnect the evaporative emission system pressure pump.
Q: Is the measured voltage 0.5 volt or less?
YES: Go to Step 13.
NO: Go to Step 19.
STEP 13. Check fuel tank differential pressure sensor connector D-09 and intermediate connector for D-14 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?
YES: Go to Step 14.
NO: Repair or replace the damaged components. Refer to Harness Connector Inspection. Reinstall the fuel tank. Refer to Fuel Tank. Then go to Step 27.
STEP 14. Check the harness wire between fuel tank differential pressure sensor connector D-09 terminal 2 and intermediate connector D-14 terminal 10 for damage.
Q: Is the harness wire in good condition?
YES: It can be assumed that this malfunction is intermittent, and reinstall the fuel tank. Refer to Fuel Tank. Then go to Step 27.
NO: Repair the damaged harness wire, and reinstall the fuel tank. Refer to Fuel Tank. Then go to Step 27.
STEP 15. Check the sensor ground at ECM connector C-115
1. Do not disconnect ECM connector C-115
2. Turn the ignition switch to the "ON" position.
3. Measure the voltage between connector C-115 terminal 92
- The measured voltage should be 0.5 volt or less.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage 0.5 volt or less?
YES: Go to Step 16.
NO: Go to Step 23.
STEP 16. Check the signal voltage at fuel tank differential pressure sensor connector D-09.
1. Remove the fuel tank. (Refer to Fuel Tank.)
2. Plug the filler hose, fuel pump feed nipple, hose I, hose M and hose R connected to the fuel tank.
NOTE: If these items are not securely plugged here, the fuel could leak in the next step.
3. Lift the fuel tank.
4. Connect special tool MB991658 to both halves of connector D-09.
5. Turn the ignition switch to the "ON" position.
6. Measure the voltage between connector D-09 terminal 1 and ground.
- The measured voltage should be between 2.0 and 3.0 volts.
7. Connect an evaporative emission system pressure pump (Miller number 6872A) to the fuel filler neck and pressurize the fuel tank.
- The fuel tank pressure reading should increase.
8. Turn the ignition switch to the "LOCK" (OFF) position.
9. Disconnect the evaporative emission system pressure pump.
Q: Is the measured voltage between 2.0 and 3.0 volts?
YES: Go to Step 17.
NO: Go to Step 20.
STEP 17. Check fuel tank differential pressure sensor connector D-09 and intermediate connector D-14 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?
YES: Go to Step 18.
NO: Repair or replace the damaged components. Refer to Harness Connector Inspection. Reinstall the fuel tank. Refer to Fuel Tank. Then go to Step 27.
STEP 18. Check the harness wire between fuel tank differential pressure sensor connector D-09 terminal 1 and intermediate connector D-14 terminal 11 for damage.
Q: Is the harness wire in good condition?
YES: It can be assumed that this malfunction is intermittent. Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction. Reinstall the fuel tank. Refer to Fuel Tank. Then go to Step 27.
NO: Repair or replace the harness wire, and reinstall the fuel tank. Refer to Fuel Tank. Then go to Step 27.
STEP 19. Measure the 5-volt reference signal at fuel tank differential pressure sensor connector D-09.
1. Turn the ignition switch to the "ON" position.
2. Measure the voltage between connector D-09 terminal 3 and ground.
- The voltage should be between 4.9 and 5.1 volts.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage between 4.9 and 5.1 volts?
YES: Go to Step 20.
NO: Go to Step 21.
STEP 20. Check fuel tank differential pressure sensor connector D-09 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?
YES: Replace the fuel tank differential pressure sensor, and reinstall the fuel tank. Refer to Fuel Tank. Then go to Step 27.
NO: Repair or replace the damaged components. Refer to Harness Connector inspection. Reinstall the fuel tank. Refer to Fuel Tank. Then go to Step 27.
STEP 21. Check fuel tank differential pressure sensor connector D-09 and intermediate connector D-14 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?
YES: It can be assumed that this malfunction is intermittent. Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction. Reinstall the fuel tank. Refer to Fuel Tank. Then go to Step 22.
NO: Repair or replace the damaged components. Refer to Harness Connector Inspection. Reinstall the fuel tank. Refer to Fuel Tank. Then go to Step 27.
STEP 22. Check the harness wire between fuel tank differential pressure sensor connector D-09 terminal 3 and intermediate connector D-14 terminal 9 for damage.
Q: Is the harness wire in good condition?
YES: It can be assumed that this malfunction is intermittent. Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction. Reinstall the fuel tank. Refer to Fuel Tank. Then go to Step 27.
NO: Repair or replace the harness wire, and reinstall the fuel tank. Refer to Fuel Tank. Then go to Step 27.
STEP 23. Check intermediate connectors C-105, C-124, C-127, and D-14, and ECM connector C-115
Q: Are the connectors and terminals in good condition?
YES: Go to Step 24.
NO: Repair or replace the damaged components. Refer to Harness Connector Inspection. Then go to Step 27.
STEP 24. Check the harness wire between ECM connector C-115 terminal 92
Q: Is the harness wire in good condition?
YES: It can be assumed that this malfunction is intermittent. Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction. Then go to Step 27.
NO: Repair the damaged harness wire. Then go to Step 27.
STEP 25. Check ECM connector C-115
Q: Are the connectors and terminals in good condition?
YES: Go to Step 26.
NO: Repair or replace the damaged components. Refer to Harness Connector Inspection. Then go to Step 27.
STEP 26. Using scan tool MB991958, check data list item 73: Fuel Tank Differential Pressure 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. Disconnect hose G from the evaporative emission canister, and plug the hose.
3. Turn the ignition switch to the "ON" position.
4. Remove the fuel cap.
5. Set scan tool MB991958 to the data reading mode.
- Item 73, Fuel Tank Differential Pressure Sensor.
- The fuel tank pressure reading on the scan tool should be -1.5 to 1.5 kPa (-0.443 to 0.443 in.Hg).
6. Connect an evaporative emission system pressure pump (Miller number 6872A) to the fuel filler neck and pressurize the fuel tank.
- The fuel tank pressure reading should increase.
7. Turn the ignition switch to the "LOCK" (OFF) position. Then disconnect scan tool MB991958.
8. Disconnect the evaporative emission system pressure pump, and reinstall the fuel cap.
9. Connect hose G to the canister.
Q: Is the fuel tank pressure between -1.5 and 1.5 kPa (-0.443 and 0.443 in.Hg)?
YES: It can be assumed that this malfunction is intermittent (Refer to How to Use Troubleshooting/Inspection Service Points - Intermittent Malfunction). Then go to Step 27.
NO: Replace the ECM
STEP 27. Perform the OBD-II drive cycle.
1. Carry out a test drive with the drive cycle pattern (Refer to Diagnostic Function - OBD-II Drive Cycle - Procedure 1 - Evaporative Emission System Leak Monitor). OBD-II Drive Cycle Pattern Lists
2. Read the diagnostic trouble code (DTC).
Q: Is DTC P0451 set?
YES: Go to Step 2.
NO: The procedure is complete.