Fuel Cap Warning Message System Troubleshooting

Fuel Cap Warning Message System Troubleshooting

Special Tools Required

- Vacuum/pressure gauge, 0-4 in.Hg 07JAZ-001000B
- Vacuum pump/gauge, 0-30 in.Hg, Snap-on YA4000A or equivalent, commercially available
When the fuel cap warning message does not go off after fuel cap tightened, or the message turned on frequently, do this troubleshooting procedure.

1. Check the fuel fill cap (the cap must say "Tighten to click"). It should turn 1/4 after it's tight, then it clicks.

Is the correct fuel fill cap installed and properly tightened?
YES - Go to step 2.

NO - Replace or tighten the cap, then go to step 13.


2. Check the fuel fill cap seal (A) and the fuel fill pipe mating surface (B). Verify that the fuel fill cap tether cord (C) is not caught under the cap.

Is the fuel fill cap seal missing or damaged, is the fuel fill pipe damaged, or is the tether cord caught under the cap?
YES - Replace the fuel fill cap or the fuel fill pipe, then go to step 13.

NO - Go to step 3.






3. Reinstall and tighten the fuel fill cap.

4. Clear the DTC with the HDS.

5. Start the engine. Hold the engine speed at 3,000 rpm without load (in P or N) until the radiator fan comes on, then let it idle for 1 minute.

6. Test drive at 45 mph (72 km/h) for 1 minute or more.

Does the fuel cap warning message come on?
YES - Go to step 7.

NO - Intermittent failure, the system is OK at this time.


7. Turn the ignition switch to LOCK (0).

8. Remove the intake air duct (air flow tube). Service and Repair

9. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B) in the engine compartment, and connect a T-fitting (C) from the vacuum gauge and the vacuum pump/gauge 0-30 in.Hg, to the EVAP canister purge valve as shown.

10. Turn the ignition switch to ON(II).

11. Apply vacuum to the hose about 2 kPa (0.6 in.Hg, 15 mmHg).

12. Select EVAP PCS ON in the INSPECTION MENU with the HDS.

Does the vacuum release immediately?
YES - Check for a blockage in the vacuum hose between the EVAP canister purge valve and the EVAP canister, then go to step 13.

NO - Replace the EVAP canister purge valve, EVAP Canister Purge Valve Replacement then go to step 13.






13. Install the parts in the reverse order of removal.

14. Turn the ignition switch to ON (II).

15. Reset the PCM with the HDS.

16. Do the PCM idle learn procedure. PCM Idle Learn Procedure

17. Start the engine. Hold the engine speed 3,000 rpm without load (in P or N) until a radiator fan comes on, then let it idle for 1 minute.

18. Test drive at 45 mph (72 km/h) for 1 minute or more.

Does the fuel cap warning message come on?
YES - Go to step 1 and recheck.

NO - Troubleshooting is complete.